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AJTorris
September 16th, 2009, 10:24
Ok well i failed smog just now. I have high Nox. Max is 1090 and i got 1805 at 15 mph and at 25 mph max is 1130 and i got 1400. What would cause this? Also my EVAP canister is plugged and tank hose is missing. I am going to fix this. And then i am missing a vacume line to the air filter box. So i need to figure out where it goes.

My question is what would cause the Nox to be so high?

silverslk
September 16th, 2009, 11:13
What were your other readings? If I remember right, NOx is caused by high combustion chamber temps. You could try colder plugs but that would raise your HC's so it depends if you have room. I would say run some seamfoam through the intake and see if it can clean some deposits out of your combustion chamber (I think I recall a build up raising chamber temps too). DO a search, there is alot of useful info and I am sure someone else will chime in too......especially if I am wrong. haha

AJTorris
September 16th, 2009, 12:37
Here are my readings....
%C02
15 MPH Meas 11.78
25 MPH Meas 11.73

%02
15 MPH Meas 3.75
25 MPH Meas 3.48
HC (ppm)
15 MPH Max 133 Ave 43 Meas 94\
25 MPH Max 104 AVE 32 Meas 97

CO (%)
15 MPH Max 0.89 Ave 0.16 Meas 0.40
25 MPH Max 1.12 Ave 0.15 Meas 0.36

NO (PPM)
15 MPH Max 1090 Ave 406 Meas 1805
25 MPH Max 1130 Ave 349 Meas 1400

AJTorris
September 16th, 2009, 17:37
well i realized that i had some vacume lines missing/broke. I replaced them and put a different EGR valve on and now it cuts out every now and then. I didnt go see if it will pass yet though.

AL BUNDY
September 16th, 2009, 19:08
What year is your jeep?

Seafoam & change the oil won't hurt. Check all the hoses to the EGR and EGR solenoid. Check the O2 sensor. I had an 88 that I had to change the O2 sensor every time before it would pass smog.

Johnnie Walker
September 16th, 2009, 21:57
Mine fails due to "non-functioning" egr.. you know anyone who will overlook this, and you can use it for your test too.

GrimmJeeper
September 16th, 2009, 22:04
my 95 failed for the same reason, if you search my username and the keyword smog you should find my thread about it. a new cat solved my problem, the one i replaced was about 4 years old. i also switched to a colder plug, champion RC9YC's

good luck, passing smog with a jeep is a real pain in the ass.

Ecomike
September 16th, 2009, 22:40
Seafoam treatment in the intake manifold will help a lot. It will help burn out the carbon build up in the combustion chambers that supports high temps that leads to higher NOx. As high as your numbers are you might want to do it twice, and add a can to about 6 gallons of gas in the gas tank, then get it on the highway and push it hard for a good 50 miles.
IF that does doesn't get you through ( I hear it works 90% of the time on NOx only problems), then look into a bad O2 sensor system (wiring, heater relay, and the sensor, get out the multi meter and run live tests) and possible need for a new cat.

You need to get the EGR working properly, cutting out is a sign of a bad EGR.

jeeperjohn
September 17th, 2009, 07:53
I barely passed smog with high N0X readings and shortly after that I took the head off and found that the valves weren't sealing well because of deposits on them. I know it's a big job but cleaning up my head and lapping the valves till they seated properly significantly improved my power and fuel economy. It may be worth your time.

badgeye
September 17th, 2009, 08:24
NOX (oxides of Nitrogen) emissions are a particulate emission that is caused by combustion chamber temps in excess of 1800 degrees. The device that is primarily responsible for lowering combustion chamber temps is the EGR valve. First I would make sure that the egr system is working properly. This is easy to do if you have a vacuum pump with a gauge. PM me for the procedure. The catalytic converter also plays a large role in reducing NOX, but the cat relys on a properly functioning O2 sensor. Testing these items is a bit more difficult and requires some specialized equipment. By looking at your emissions readings and performing a Lambda calculation it appears that the vehicle is running a little lean. This could cause the Catalytic Converter to stop working. I recommend fixing any vacuum leaks. And make sure EGR is functional. Top end cleaning could not hurt as increased compression due to carbon buildup will cause NOX. Do not use any heat range plug other than the one specified. Plug heat range has no effect on combustion chamber temp, only flame propagation, and this is not your problem.

Goatman
September 17th, 2009, 08:31
I was going to tell you to talk to Eric, but I see he just answered. :)

PM him, and get his number.

Ecomike
September 17th, 2009, 08:53
NOX (oxides of Nitrogen) emissions are a particulate emission that is caused by combustion chamber temps in excess of 1800 degrees. The device that is primarily responsible for lowering combustion chamber temps is the EGR valve. First I would make sure that the egr system is working properly. This is easy to do if you have a vacuum pump with a gauge. PM me for the procedure. The catalytic converter also plays a large role in reducing NOX, but the cat relys on a properly functioning O2 sensor. Testing these items is a bit more difficult and requires some specialized equipment. By looking at your emissions readings and performing a Lambda calculation it appears that the vehicle is running a little lean. This could cause the Catalytic Converter to stop working. I recommend fixing any vacuum leaks. And make sure EGR is functional. Top end cleaning could not hurt as increased compression due to carbon buildup will cause NOX. Do not use any heat range plug other than the one specified. Plug heat range has no effect on combustion chamber temp, only flame propagation, and this is not your problem.


Just FYI, NOx is not a particulate, it is a gas. Also, while you are right on the purpose of the EGR, most jeeps can meet NOx emissions limits easily with out the EGR, in fact it was deleted on HO 4.0s. EGRs over time, and fubared O2 sensor systems that let the engine run rich tend to build up lots of carbon in the combustion chamber, that leads to high NOx emissions, as we both pointed out. He does need to fix the EGR to fix the hesitation/miss he noted that showed up after reinstalling the EGR, as that might re-fail it also.

badgeye
September 17th, 2009, 10:39
Just FYI, NOx is not a particulate, it is a gas. Also, while you are right on the purpose of the EGR, most jeeps can meet NOx emissions limits easily with out the EGR, in fact it was deleted on HO 4.0s. EGRs over time, and fubared O2 sensor systems that let the engine run rich tend to build up lots of carbon in the combustion chamber, that leads to high NOx emissions, as we both pointed out. He does need to fix the EGR to fix the hesitation/miss he noted that showed up after reinstalling the EGR, as that might re-fail it also.


When the EGR was deleted the camshaft overlap was changed to trap exhaust gas in the combustion chamber. A jeep 4.0 is not capable of easily passing NOX without some provision for reduction of combustion chamber temp. At least thats the way it was explained to me by the Chrysler engineer that taught the Jeep factory advanced driveability class that I took. While it is true that thermal NOx (or simple NO) is a gas, it is my understanding that the formation of Fuel NOx includes some particulate matter as a result of the combustion of the char portion of the fuel, which is nearly 100% carbon. Goatman and I were just discussing this very topic night before last. The particulars of the gas composition really are inconsequential to the discussion, I was just trying to answer his question, "what would cause the NOX to be so high?" And maybe give him some advice that would help him get it fixed.

Goatman
September 17th, 2009, 11:11
Just FYI, NOx is not a particulate, it is a gas. Also, while you are right on the purpose of the EGR, most jeeps can meet NOx emissions limits easily with out the EGR, in fact it was deleted on HO 4.0s. EGRs over time, and fubared O2 sensor systems that let the engine run rich tend to build up lots of carbon in the combustion chamber, that leads to high NOx emissions, as we both pointed out. He does need to fix the EGR to fix the hesitation/miss he noted that showed up after reinstalling the EGR, as that might re-fail it also.

Ahh, you're talking to a certified smog tech, past Jeep dealership shop foreman, and the best (smartest) auto diagnostic tech I have ever known or worked with. Eric finds and fixes the stuff others can't get done. I'd consider him an expert on the subject.

Ecomike
September 17th, 2009, 15:29
Ahh, you're talking to a certified smog tech, past Jeep dealership shop foreman, and the best (smartest) auto diagnostic tech I have ever known or worked with. Eric finds and fixes the stuff others can't get done. I'd consider him an expert on the subject.

Always nice to know what people's credentials are. Even the best of us can things wrong, except me of course, LOL.:laugh3:

Eric sounds like me. I am one of those people known for taking apart something I have never seen, with no training or manuals, and fixing it. Chemical Engineering, pollution, environmental engineering is my area. While I am not an absolute expert on NOx, I know a few things, and know how and where to figure some of the more obscure details, but I am not a combustion engineer, so there are grey areas for me, as I am sure there are for you guys.

Some of what I learned about Jeep NOx and jeep EGRs I learned 5-90, who has proven first hand that the Renix jeep has lower NOx emissions with out the EGR, but I have never chalenged him on the test conditioins, I only know that the conditions were the standard California (near LA?) test methods and conditions, which might be different from what Chrysler was forced to use by EPA 20 years ago.

Ecomike
September 17th, 2009, 16:14
When the EGR was deleted the camshaft overlap was changed to trap exhaust gas in the combustion chamber. A jeep 4.0 is not capable of easily passing NOX without some provision for reduction of combustion chamber temp. At least thats the way it was explained to me by the Chrysler engineer that taught the Jeep factory advanced driveability class that I took. While it is true that thermal NOx (or simple NO) is a gas, it is my understanding that the formation of Fuel NOx includes some particulate matter as a result of the combustion of the char portion of the fuel, which is nearly 100% carbon. Goatman and I were just discussing this very topic night before last. The particulars of the gas composition really are inconsequential to the discussion, I was just trying to answer his question, "what would cause the NOX to be so high?" And maybe give him some advice that would help him get it fixed.

Wasn't trying to jerk your chain, you obviously have some excellant training, knowledge and experience to be proud of, I was just trying to teach some basic chemistry / terminolgy, as the term caught my attention, and being a chemical engineer, and hanging out in a tech forum here, it got my attention.

Very interesting to hear that the cam is different between HO and Renix, and at least part of the why! Thanks. I made some comments below in another post about 5-90's tests on live California emissions test equipment that showed equal or lower NOx emissions on the same engine without the EGR, versus with it. It is a pet peave of his, he claims he has even tried to convince the State people that the EGR is more trouble than it is worth on the renix 4.0 at least.

NOx means NO, NO2, and NO3, all of which are gasses. The X is just an algebraic variable, short hand for 1,2 or 3. When measuring a pollutant like NOx, they are only measuring the number of N atoms, that are bound to O (oxygen) atoms by measuring the number of N to O bounds which absorb a specific wavelength of light, and the loss of that wavelength of light (missing photons) passing through a sample is detected to quantify the number of NOx gas molecules in the exhaust.

While the particulate is part of the air pollution story it is not what is measured and quantified in the engine exhaust to my knowledge, and I deal with the chemcal plant end of that sort of lab equipment where they also monitor and measure NOx emissions. The NOx reacts with VOCs (molecules of gasoline are VOCs, and natural VOCs like turpines from local pine trees) and forms particles that are called smog. To my knowledge the particulate formation, smog happens after the NOX hits the atmosphere and cools. The smog (particulate) formation is typical trigger by UV light from the sun hitting an NOx or VOC molecule.

VOC = Volotile Organic Compound

Back on topic, I have been told by several experts, including a local Texas auto emissions tester (*) here in Houston, and 5-90, that running a good cleaner through the intake and gas tank (dual treatment) to clean the carbon build up in the intake, and especiallly the combustion chamber out (*)"has never failed to fix and pass a high NOx only failed vehicle" in his experience. However, the tests in California (LA), are tougher than here so who knows, but if the CAT is working well enough to keep the CO and hydrocabons with CA limits, chances are cleaning all the crap out of the combustion chamber may do the trick for him on NOx.

badgeye
September 17th, 2009, 16:32
The shop where I work is a California Gold Shield Station and is authorized to do Consumer Assistance Program repairs. This means that the California Bureau of Automotive Repair has final say on the methods of diagnosis and repair that we use. In the case of an emissions failure the first thing that we must do is determine if the vehicle is in fuel control. In other words is the fuel injection system operating close to stoichometric ratio (14.7:1 air fuel ratio by weight) The way that we make this determination is by using a Lambda calculator. Lambda is a term that has been used by the Germans for years, in fact they refer to an O2 sensor as a Lambda sensor. The cool thing about Lambda calculations is that they are accurate no matter what the other smog control systems are doing. Even if the cat is bad and you are reading post cat emissions, the Lambda calc will still be good. Just take the vehicles emission readings and plug them into a Lambda calculator. I use the one at www.Iatn.net (http://www.Iatn.net) but there is one you can use at www.smogsite.com/calculators.html (http://www.smogsite.com/calculators.html) without being a member. The best Lambda reading is 1 but anything from .98 to 1.02 is acceptable. If the Lambda reading is within these numbers it is safe to assume that the vehicle is in fuel control. I always use a lab scope to check O2 sensor amplitude and modulation because a lazy O2 sensor can keep the vehicle in fuel trim but still allow Catalytic efficiecy to fall below threshold. If vehicle is determined to be in fuel trim emissions systems are checked. Catalytic converters are checked using a cranking CO2 test. The cat is heated by holding throttle at 2500 rpms until emissions drop to their lowest level(this test requires a 5 gas analyzer) then ignition system is disabled and engine is cranked allowing fuel to go through cylinders and into catalytic converter. HC emissions should not exceed 500 ppm and CO2 emission (product of combustion) should exceed 12 %. If both of these parameters are not met, cat is probably bad. This is the only test that is accepted by the B.A.R. to condemn a cat besides intrusive testing (drilling a hole before and after)

Sorry to the original poster if I hijacked your thread. Hopefully there is something here you can use. Or p.m. me if I can be of more help.

Ecomike
September 17th, 2009, 20:17
I need to drag you over to one of my older O2 sensor threads in the OEM forum here.

Thanks for posting the links!

There is also an OEM forum thread where I have asked owners to post their emissions test data, building a sort of XJ data base on pass / fail results.

Do you all run live running tests on OBD-II years there? Here in Texas, if the computer is clean of codes you pass, no tests.

badgeye
September 17th, 2009, 21:25
I need to drag you over to one of my older O2 sensor threads in the OEM forum here.

Thanks for posting the links!

There is also an OEM forum thread where I have asked owners to post their emissions test data, building a sort of XJ data base on pass / fail results.

Do you all run live running tests on OBD-II years there? Here in Texas, if the computer is clean of codes you pass, no tests.

I am assuming you mean dynamometer testing. Here it is known as ASM (acceleration simulation mode) we do one test at 15 mph and one at 25 mph. The 15 mph is at higher load than the 25 mph. Our Test Analyzer System (T.A.S.) is also hooked to the diagnostic link to check for codes. The vehicle must have no codes and have most of the monitors run or the vehicle will fail.Bakersfield is located at the south end of the San Joaquin Valley, and it has been deemed a "severe non attainment area" which means our pollution is every bit as bad as the L.A. basin. There are some surounding rural areas that are TSI (two speed idle test) we see some of those vehicles here in town. Those vehicles require functional EGR testing. ASM tests do not get EGR functional tests because we measure NOx under load on those vehicles. All wheel drive vehicles and vehicles with non disengageable traction control also get TSI tests. The rules are the same for pre OBD2 vehicles except those vehicles also get a functional evaporative emissions system test where we hook up a machine to the fuel tank, pinch off the vapor line at the evap canister and check evap system integrity.

We have several levels of government here where air quality is concerned. The Federal Government is really the least of our concerns because The California Air Resources Board (C.A.R.B) regulations are much more stringent. Those laws are administered by the Bureau of Automotive Repair (B.A.R) which is the executive branch of the Department of Consumer Affairs. Then here in the San Joaquin Valley we have the Valley Air Resources Board, which is actually more concerned with industrial emissions and Dust (PM10) because this is a very agricultural area.

badgeye
September 17th, 2009, 21:36
I need to drag you over to one of my older O2 sensor threads in the OEM forum here.

Thanks for posting the links!

There is also an OEM forum thread where I have asked owners to post their emissions test data, building a sort of XJ data base on pass / fail results.

Do you all run live running tests on OBD-II years there? Here in Texas, if the computer is clean of codes you pass, no tests.

I am assuming you mean dynamometer testing. Here it is known as ASM (acceleration simulation mode) we do one test at 15 mph and one at 25 mph. The 15 mph is at higher load than the 25 mph. Our Test Analyzer System (T.A.S.) is also hooked to the diagnostic link to check for codes. The vehicle must have no codes and have most of the monitors run or the vehicle will fail.Bakersfield is located at the south end of the San Joaquin Valley, and it has been deemed a "severe non attainment area" which means our pollution is every bit as bad as the L.A. basin. There are some surounding rural areas that are TSI (two speed idle test) we see some of those vehicles here in town. Those vehicles require functional EGR testing. ASM tests do not get EGR functional tests because we measure NOx under load on those vehicles. All wheel drive vehicles and vehicles with non disengageable traction control also get TSI tests. The rules are the same for pre OBD2 vehicles except those vehicles also get a functional evaporative emissions system test where we hook up a machine to the fuel tank, pinch off the vapor line at the evap canister and check evap system integrity.

We have several levels of government here where air quality is concerned. The Federal Government is really the least of our concerns because The California Air Resources Board (C.A.R.B) regulations are much more stringent. Those laws are administered by the Bureau of Automotive Repair (B.A.R) which is the executive branch of the Department of Consumer Affairs. Then here in the San Joaquin Valley we have the Valley Air Resources Board, which is actually more concerned with industrial emissions and Dust (PM10) because this is a very agricultural area.

Goatman
September 18th, 2009, 09:07
My XJ failed a smog test for high NOx, due totally to bad EGR, and the NOx was high. Resolved the EGR problem and it passed. I've known others to do the same. I've been a manager at car dealerswhips for many, many years, and personally oversee the used car reconditioning departments dealing with smog testing vehicles on a daily basis. I've run across many EGR issues with failing smog. Don't really know what 5-90's issues are, never seen what he's written.

Ecomike
September 18th, 2009, 09:16
My XJ failed a smog test for high NOx, due totally to bad EGR, and the NOx was high. Resolved the EGR problem and it passed. I've known others to do the same. I've been a manager at car dealerswhips for many, many years, and personally oversee the used car reconditioning departments dealing with smog testing vehicles on a daily basis. I've run across many EGR issues with failing smog. Don't really know what 5-90's issues are, never seen what he's written.

Put simply, 5-90 has taken a working Renix and put a plate between the EGR and the intake manifold where the gasket goes, sealing off the EGR from recycling exhaust gas into the inatke and passed the toughest California emissions tests, proving that is not needed to pass. He has spoken about this many times in OEM forum threads here for several years now.

I won't arguing that a failing, bad, defective, stuck open EGR would cause enough trouble to make one fail.

Goatman
September 18th, 2009, 09:29
Mine was actually blocked off in a slightly used motor that I bought. We didn't know it, did all kinds of things to get the NOx down, for a number of days. The tech was pulling his hair out and finally realized there was no flow through the EGR, and found it blocked off at the exhaust manifold, impossible to recirculate any exhaust gasses. Opened it up and it passed smog immediately.

Just my personal experience. I guess mine proves that it is needed to pass. :)

Ecomike
September 18th, 2009, 21:59
Mine was actually blocked off in a slightly used motor that I bought. We didn't know it, did all kinds of things to get the NOx down, for a number of days. The tech was pulling his hair out and finally realized there was no flow through the EGR, and found it blocked off at the exhaust manifold, impossible to recirculate any exhaust gasses. Opened it up and it passed smog immediately.

Just my personal experience. I guess mine proves that it is needed to pass. :)


Might be interesting to start an OEM forum thread and ask how people passed NOx tests (and at what levels if they know), with a Renix that had the EGR blocked or disabled.

May not get many replies, but you never know.

I will continue to keep an open mind about it, both ways. My thinking is if there are other problems, like the engine is running hot, or a little lean, then EGR might make the difference in a pass fail. I do know that 5-90. like me runs a cooler thermostat, bigger radiator,.....and those differences might make a difference on the EGR, no EGR NOx tests. He also does not run his with a knock sensor, which also might let his run a little cooler, thus reducing NOx. Too many other variables, which is part of the problem.

Goatman
September 20th, 2009, 14:51
And since you can't pass the visual smog without the EGR anyway, the whole subject is a great big non-issue from my perspective......due the amount of attention it's received the last couple of days and that's it. Moving on......

:)

5-90
September 20th, 2009, 15:11
Put simply, 5-90 has taken a working Renix and put a plate between the EGR and the intake manifold where the gasket goes, sealing off the EGR from recycling exhaust gas into the inatke and passed the toughest California emissions tests, proving that is not needed to pass. He has spoken about this many times in OEM forum threads here for several years now.

I won't arguing that a failing, bad, defective, stuck open EGR would cause enough trouble to make one fail.

Close, Mike.

This actually happened shortly after I'd got my 87, and have to have it smogged (again.) The EGR system was NF, but HC, CO, and NOx were all well within limits. The only reason the "tech" knew that the EGR was NF was when he pulled a vacuum on it and it didn't have any effect on engine operation.

I had to get a new EGR valve (OEMR, $150 or so - and servicing that thing was a bear...) and get a retest. HC and CO both jumped, without any significant change in NOx.

That was when I started writing CARB - since they're mandating the use of a device that, in some applications, actually makes things worse instead of better. I also posited that a system from the 1940's and 1950's, and used on military aircraft, would be a better solution.

That solution? Water/MeOH fogging. It wouldn't crap things up with carbon, it would work better to keep combustion temperatures down, the MeOH would work as a "primer" for the fuel combustion (keeping HC and CO down,) and would be a better approach overall.

I ended up being invited to a workshop for local smog guys when SCII was going to roll out. Problem is, I ended up embarassing the Regional Director and Acting State Director rather badly in that workshop - I had more answers to questions than they had, and they couldn't answer any of mine.

I'm firmly convinced that my XJs were the first in the state to be "profiled" as "gross polluters" - I was getting sent to Test Only stations well before we started complaining about it here.

I do run a Knock sensor (no reason not to,) but I do not run any thermostat - even with a 160* piece, Beck still overheats in short order. I don't know why - I've replaced damned near everything in the cooling system anyhow - but it's just one of those quirks. I've run across three vehicles in the last thirty years that had that little quirk, and I've owned all three (1980 Honda Accord 1.8L CVCC, 1985 Chevvy Cavalier 122ci, and 1988 Jeep Cherokee 242ci. NB: Beck is the only one out of the five RENIX rigs I've had that wouldn't run with a thermostat in place without overheating!) That makes it a known quirk, but rare. And I do run a Modine three-row.

What's the source for the difference in cam grind on either side of 1990/1991? From what I've seen (I'll have to find my source and cite it...) the grind remained the same, but it may have been installed a bit off-centre (no information on that.) I know the head was modified fairly significantly, but I don't think anything was done to promote reversion (which is a "poor man's approach" to EGR - instead of piping it back through the intake, some of the exhaust gas just doesn't leave the chamber - or get into the port and bounced back.)

The only emissions control system that really works as designed, and does what it's supposed to do consistently is the EVAP control setup. I don't honestly consider the HEGO feedback loop an "emissions control" device, it's more of a fuel economy/fuel efficiency control mechanism.

xj_dummy
September 20th, 2009, 20:12
You might want to put the original thermostat back in because I have heard that if its not the correct temp if will throw your emissions off too.

5-90
September 20th, 2009, 20:15
You might want to put the original thermostat back in because I have heard that if its not the correct temp if will throw your emissions off too.

I'd love to, except Beck overheats when I put any thermostat in. Runs a little cooler than spec without it, and no harmful effects on emissions (they're comparable to pass results on my old 87 and both of the 89s.) As I said, it's a quirk - rare, but not unheard of. Most people go their whole lives without finding a vehicle like this, I just happen to have owned three of them (and yes, I've renewed the entire cooling system, and flushed out the bits I couldn't replace outright, like the engine block. I'm damned sure it's not something I've done.)

Ecomike
September 20th, 2009, 21:35
The only real fluid mechanics effect of no thermostat is that the coolant pressure on the inlet side of the radiator is a little bite higher with out a thermostat than it would be with a thermostat. The thermosat does restrict flow and does cause a small pressure drop across the thermostat. At the head pressures an automotive coolant pump develops, the thermostat is a significant restriction, and does restrict flow.

Only problem with MeOh/H2O is getting Joe and Jane Q. Public to refill the container and pay for the DI water and MeOH.

DesertRunner
September 20th, 2009, 21:40
my cherokee runs hot with anything besides a 180 in it! it constantly runs at 212.... gonna toss a larger trans cooler on it see it it makes a difference!

on the high nox readings i built a stroker motor that wouldnt pass smog due to high nox 1500ish at 15mph i went to the local jy pulled injectors out of a ford f350 with the 460ci motor "blue top" brought my nox to 73! i had already replaced the cat and egr to no avail! happy the injectors took care of that problem!

5-90
September 20th, 2009, 21:44
The only real fluid mechanics effect of no thermostat is that the coolant pressure on the inlet side of the radiator is a little bite higher with out a thermostat than it would be with a thermostat. The thermosat does restrict flow and does cause a small pressure drop across the thermostat. At the head pressures an automotive coolant pump develops, the thermostat is a significant restriction, and does restrict flow.

Only problem with MeOh/H2O is getting Joe and Jane Q. Public to refill the container and pay for the DI water and MeOH.

The thermostat bit I quit worrying about years ago. I may eventually try a restrictor plate in there, just to see what happens, but I'm honestly not sure I want to bother.

I'm not saying that the water/MeOH system will work for everyone - as you've pointed out (indirectly,) there are people out there who don't even know that fluids occasionally want changing. (Granted, they shouldn't be driving in the first place.) However, there are those of us who can tune an engine to run better/cleaner than the factory could - because what the factory usually ends up doing is striking a compromise between effectiveness, long-term "reliability," and user/owner apathy. But, if there are those of us out here who can modify a system (or eliminate it entirely!) and improve things, there is no reason why we should not be able to.

I have no problem with the idea of the Smog Check prograramme, just with its implementation. The idea is to reduce harmful emissions, and I don't see how limiting our ability to do so is going to help. Eliminate the visual (which usually has sod-all to do with tailpipe emissions anyhow,) mandate a five-gas analysis everywhere, and give discounts on registration on a sliding scale to those of us who can tune older vehicles, keep them on the road, and consistently have better emissions numbers than newer vehicles.

If I'm going to have to fork over $89.95 (test) + $7.00 (cert - if I pass, which makes very little sense...) to get a registration that runs me $45, there's something wrong.

And, having to pay extra because you pass is just plain stupid. It's supposed to be for a "certificate" - has anyone here ever seen one of these? All I get is an invoice and a copy of the report printed out from the machine, and I get that whether I pass or fail.

If it's transmitted electronically, then it damned sure don't cost seven dollars to send it, even on an old 300 BAUD MODEM...

badgeye
September 20th, 2009, 22:50
Close, Mike.

This actually happened shortly after I'd got my 87, and have to have it smogged (again.) The EGR system was NF, but HC, CO, and NOx were all well within limits. The only reason the "tech" knew that the EGR was NF was when he pulled a vacuum on it and it didn't have any effect on engine operation.

That was when I started writing CARB - since they're mandating the use of a device that, in some applications, actually makes things worse instead of better. I also posited that a system from the 1940's and 1950's, and used on military aircraft, would be a better solution.

What's the source for the difference in cam grind on either side of 1990/1991? From what I've seen (I'll have to find my source and cite it...) the grind remained the same, but it may have been installed a bit off-centre (no information on that.) I know the head was modified fairly significantly, but I don't think anything was done to promote reversion (which is a "poor man's approach" to EGR - instead of piping it back through the intake, some of the exhaust gas just doesn't leave the chamber - or get into the port and bounced back.)

The only emissions control system that really works as designed, and does what it's supposed to do consistently is the EVAP control setup. I don't honestly consider the HEGO feedback loop an "emissions control" device, it's more of a fuel economy/fuel efficiency control mechanism.

I am assuming you are in California, but if you are in an enhanced area the "tech" should not be performing a functional EGR test on a loaded mode test. Functional EGR is not part of an ASM test. There is no place in the test sequence to fail it for functional and there is no NOx reading on a TSI test. The info on the camshaft came from a Chrysler engineer at the training center in Fontana Ca. I also verified that the part numbers are different for different year vehicles. Keeping some exhaust in the cylinder is actually an excellent (and widespread) way of cooling the combustion chamber. It prevents all of that carbon from being recirculated through the intake, it never stops working from clogged passages or ruptured diaphragms, no parts to replace, cannot be messed with by "tuners" and streamlines the inspection process. As far as the function of the O2 sensor feedback loop, modern computers are more than fast enough (especially with the advent of Controller Area Network systems) to hold the engine at stoichometric ratio, 14.7:1, without any switching at all from the O2 sensor. The problem is that the reduction bed of the catalytic converter relys on the oxygen that is present during the "lean" stage of O2 sensor operation to reduce emissions.


I'm not saying that the water/MeOH system will work for everyone - as you've pointed out (indirectly,) there are people out there who don't even know that fluids occasionally want changing. (Granted, they shouldn't be driving in the first place.) However, there are those of us who can tune an engine to run better/cleaner than the factory could - because what the factory usually ends up doing is striking a compromise between effectiveness, long-term "reliability," and user/owner apathy. But, if there are those of us out here who can modify a system (or eliminate it entirely!) and improve things, there is no reason why we should not be able to.

I have no problem with the idea of the Smog Check prograramme, just with its implementation. The idea is to reduce harmful emissions, and I don't see how limiting our ability to do so is going to help. Eliminate the visual (which usually has sod-all to do with tailpipe emissions anyhow,) mandate a five-gas analysis everywhere, and give discounts on registration on a sliding scale to those of us who can tune older vehicles, keep them on the road, and consistently have better emissions numbers than newer vehicles.

If I'm going to have to fork over $89.95 (test) + $7.00 (cert - if I pass, which makes very little sense...) to get a registration that runs me $45, there's something wrong.

And, having to pay extra because you pass is just plain stupid. It's supposed to be for a "certificate" - has anyone here ever seen one of these? All I get is an invoice and a copy of the report printed out from the machine, and I get that whether I pass or fail.

If it's transmitted electronically, then it damned sure don't cost seven dollars to send it, even on an old 300 BAUD MODEM...

There is no doubt that the system you propose to reduce NOx would be far superior to the current one. The trouble comes with maintaining it. As you mentioned, people simply do not want to maintain their vehicles, or they want to screw with systems they dont understand to try and make more power. Do you only pay $7 for a certificate, we pay $8.25 for them, and we don't make a dime on them. The state prevents us from marking them up. The cost to transmit them is actually around $2, and that comes out of the test fee, that is the cost that the state charges for the 2 times during the test that the TAS machine contacts the VID. As far as older vehicles being as clean as new ones, most of the vehicles that I see that are 2000 and later are well below averages on their tests. I routinely see PZEV and ULEV vehicles that are 2 or 3 ppm HC & CO and zero NOx,(without an EGR valve) and I have seen several Hondas and Toyotas that were zero emissions. In 20 years as a smog "tech" I have never seen any straight 6 engine even approach that, much less an old Renix system with an EGR valve. :D

badgeye
September 20th, 2009, 23:02
To the O.P........................how are things going with your smog check? I have some time this week if you would like some help with it.

5-90
September 20th, 2009, 23:38
my cherokee runs hot with anything besides a 180 in it! it constantly runs at 212.... gonna toss a larger trans cooler on it see it it makes a difference!

on the high nox readings i built a stroker motor that wouldnt pass smog due to high nox 1500ish at 15mph i went to the local jy pulled injectors out of a ford f350 with the 460ci motor "blue top" brought my nox to 73! i had already replaced the cat and egr to no avail! happy the injectors took care of that problem!

210-215*F is "spec" operating temperature for the thing, that's not odd at all.

The "temeprature" of the thermostat doesn't have anything at all to do with the ultimate operating temperature of the engine, all that it refers to is the temperature at which it opens and allows coolant flow to the radiator.

A 160* thermostat opens at 160*F - but doesn't change the op temp.
A 180* thermostat opens at 180*F - and you probably already get the idea.

Typical thermostats are rated for 160*, 180*, 192-195*, and (rare, but I've seen them) 205-210* for special applications.

Using the Ford injectors would make for more efficient combustion - Ford V8 and Chevvy LT1 injectors have four nozzles to dispense fuel (vice a single,) so the droplets are finer and therefore combust more readily when ignited. Recall that liquid gasoline is barely flammable, while evapourated gasoline borders on explosive. Therefore, you want your gasoline delivered in as fine a mist as practically possible - if you could evapourate it and deliver it to the cylinder that way, it would be ideal. Which is why gaseous/vapour fuels work so well - you can't get much more finely divided than that! (Historical note - the Diesel-cycle engine was originally designed to run on coal dust, before being converted to - I believe - peanut oil, then petroleum. That's why you don't need much to convert one to run on WVO, or not much work to make WVO into Greasel.)

AJTorris
September 22nd, 2009, 20:44
ya man that would be great. I am free any day any time usually now because i just got laid off. Ill send you a pm with my number if you want to give me a call. my name is AJ

1990JEEPXJ
September 24th, 2009, 18:01
i know its off topic, but semi related. my little brothers 91 honda accord failed due to high NOx again. it has a new EGR that works and was verified with a vacuum gauge. it sems like seafoam or a similar product should be run through as good insurance. any other tips? everything else is good with regards to the emissions numbers.

5-90
September 24th, 2009, 18:33
There is no doubt that the system you propose to reduce NOx would be far superior to the current one. The trouble comes with maintaining it. As you mentioned, people simply do not want to maintain their vehicles, or they want to screw with systems they dont understand to try and make more power. Do you only pay $7 for a certificate, we pay $8.25 for them, and we don't make a dime on them. The state prevents us from marking them up. The cost to transmit them is actually around $2, and that comes out of the test fee, that is the cost that the state charges for the 2 times during the test that the TAS machine contacts the VID.


I don't have a great deal of time at the moment, so I'll have to reply more fully later. Another question for you tho - so, that "Smog Cert" fee is simply passed along by you guys, from the State itself? (Yeah, I'm in San Jose.)

What is their justification for charging the fee, and how do they arrive at two dollars for transmittal? Once it's done as digital data, and since it's all text data (at least, from the reports I've seen,) it shouldn't take anywhere near as long to transmit - either with a 56kBAUD MODEM, or using some variety of broadband (given the wealth of service data online, the latter makes more sense for a shop that does repairs as well.)

So, transmitting a day's worth of certs and data shouldn't cost more than two dollars, much less a single cert. Have they explained to you how they arrive at that asinine charge (I call it asinine - since it's assessed against you if you pass rather than if you fail - not that I care for it either way.)

badgeye
September 24th, 2009, 21:33
I don't have a great deal of time at the moment, so I'll have to reply more fully later. Another question for you tho - so, that "Smog Cert" fee is simply passed along by you guys, from the State itself? (Yeah, I'm in San Jose.)

What is their justification for charging the fee, and how do they arrive at two dollars for transmittal? Once it's done as digital data, and since it's all text data (at least, from the reports I've seen,) it shouldn't take anywhere near as long to transmit - either with a 56kBAUD MODEM, or using some variety of broadband (given the wealth of service data online, the latter makes more sense for a shop that does repairs as well.)

So, transmitting a day's worth of certs and data shouldn't cost more than two dollars, much less a single cert. Have they explained to you how they arrive at that asinine charge (I call it asinine - since it's assessed against you if you pass rather than if you fail - not that I care for it either way.)

In the old days there was a printer on the machine that would actually print out a smog certificate. So when you got your smog check, you would get your vehicle inspection report and a smog certificate that you would send to the DMV. When the machine would run low on certificates someone would have to drive to the BAR office and buy more certificates. Now the certificate is transmitted electronically by a dial-up modem. Each communication takes about 1 minute or so. The first communication is at the beginning of the test when the TAS (analyzer) queries the VID for information about the car (VIN/license # match, previous test data) The second communication occurs at the end of the test when the test information is transmitted to the VID. The communication fee is levied by the company that subcontracts the communications.
The certificate fee is charged by the state. Every time we do a smog the machine tells us how many "certificates" are left, and when the count gets below 10 the computer automatically orders 50 more and debits our bank account for the total. And yes, we get charged for that communication too. The price for the certificate is set by the state, and it is not legal to mark it up. That is why smog prices vary, but certificate prices do not. At least noone loses their certificates anymore and they can't be stolen, which was actually fairly common, and cannot be forged.:D

You know, maybe they have just been charging it for so long that nobody questions it anymore. The smog station certainly would not miss it. There are 4 TAS machines in the shop where I work, which means that at any given time we have as much as $1600 worth of "inventory" that has zero profit potential. There was a time that if you wanted to bring a car into California you had to pay a $350 "environmental impact fee" but that was eventually deemed unconstitutional.

5-90
September 24th, 2009, 22:25
In the old days there was a printer on the machine that would actually print out a smog certificate. So when you got your smog check, you would get your vehicle inspection report and a smog certificate that you would send to the DMV. When the machine would run low on certificates someone would have to drive to the BAR office and buy more certificates. Now the certificate is transmitted electronically by a dial-up modem. Each communication takes about 1 minute or so. The first communication is at the beginning of the test when the TAS (analyzer) queries the VID for information about the car (VIN/license # match, previous test data) The second communication occurs at the end of the test when the test information is transmitted to the VID. The communication fee is levied by the company that subcontracts the communications.
The certificate fee is charged by the state. Every time we do a smog the machine tells us how many "certificates" are left, and when the count gets below 10 the computer automatically orders 50 more and debits our bank account for the total. And yes, we get charged for that communication too. The price for the certificate is set by the state, and it is not legal to mark it up. That is why smog prices vary, but certificate prices do not. At least noone loses their certificates anymore and they can't be stolen, which was actually fairly common, and cannot be forged.:D

You know, maybe they have just been charging it for so long that nobody questions it anymore. The smog station certainly would not miss it. There are 4 TAS machines in the shop where I work, which means that at any given time we have as much as $1600 worth of "inventory" that has zero profit potential. There was a time that if you wanted to bring a car into California you had to pay a $350 "environmental impact fee" but that was eventually deemed unconstitutional.

I remember the "environmental impact fee" - yet another of the asinine facets of the whole damned programme.

NB: I have no problem with the basic idea, nor with the programme proper in theory. It is the execution and implementation of the programme that has gone stupid.

And, if the certs are now "paperless," why charge for them? Wait - dumb question - since they're paperless, that's almost pure profit for CA for no good reason (as well as charging you guys for the comms - which is also asinine...) and we all know how Scrappymento just loves to spend other people's money. One is suddenly forced to wonder if it is allocated for anything specific, or if it just goes into the General Fund (therefore, congresscritter pay and perquisites.) Hmm...

So let's see -
- CA overcharges for the comms, because of the contractor (which probably is not needed, given the automation available now.)
- CA overcharges for the certificates - especially since they're paperless.
- CA specifies a certain variety of tester - which means you get overcharged for the wretched thing (something akin to automotive coverage - you've got to have it, and they screw you as hard as they think they can get away with...) and you have to pass some of that along to us so you can pay for the wretched thing. What did the last generation of standalone testers run - something like $30K? How about the in-floor rollers - I'm willing to bet those are up around $100-125K, once you factor in all of the digging and cement work (maybe more?) At least you have a captive market...

Last time I let a tech drive my rig on a dyno (I'd bought it in Sacramento - ESC area. Had to have the ESC done down here the first time...) at Greenslip, the guy stalled it three times on the dyno! The manager came out because I was yelling at the tech; I knew the clutch was good when I drove it down, and if he burned it or glazed it, he'd be paying personally for the replacement and my time to put it in...

I've since told all of the shops I've swapped in an AWD tcase, and now get the TSI test instead of the rolling test. I'd really like to have a free hand in tuning and modifying the engine (as long as it passes smog, what would be the problem? Who cares how I do it?) since I'm one of those people who actually tries to take care of his vehicles, but the State obviously doesn't feel that way, and they don't trust anyone.

Therefore, I don't trust them. After having talked to the Directors at that workshop, I'm convinced that none of them actually know what they're about and are just political appointees (simply because knowledge of the subject matter doesn't seem to be a requirement at all. At least, they didn't show any - although the smog guys that were there seemed to understand what I was saying...)

Any programme with this much inflexibility built into it needs to be scrapped and rewritten. The CARB EO process isn't much better - from what I've seen.

badgeye
September 24th, 2009, 22:35
I believe the machines w/dyne were originally around $100k, but they are getting old. These are the BAR97 machines. They do not have the capability of communicating with CAN BUS(controller area network) cars. Since nearly all new cars are CAN BUS, there will be new machines in 2010. So far we have not heard, but there does not appear to be any need for new dynes. I would, however, expect that the price of getting a smog will go up. The state does not tell us which machine to buy, but obviously the machine must be approved. We have 3 different brands of machine in the shop where I work.

DesertRunner
September 25th, 2009, 22:11
've since told all of the shops I've swapped in an AWD tcase, and now get the TSI test instead of the rolling test

please pardon my ignorance but what would this tsi test consist of?

5-90
September 25th, 2009, 23:58
please pardon my ignorance but what would this tsi test consist of?

Two-speed idle. What Smog Check used to be, when they'd let the vehicle sit on the ground and take readings at 1500 and 2500rpm.