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Test Only Smog help?
- Thread starter cracker
- Start date
ruggedjeep
NAXJA Forum User
- Location
- Sherman Oaks
:eyes: 
We're shit outta luck dude. We've had no luck either
We're shit outta luck dude. We've had no luck either
- Location
- Hammertown, USA
Cracker you gotta ask me about this stuff in person. As I have told you before, I can source -ANYTHING-.
As I have told you before, I can source -ANYTHING-.
sintax
NAXJA Forum User
- Location
- Corona, CA
convert it to run on propane, and once you get it approval from the BAR on that, you are exempt from any further tests, just convert it back. You can find all the parts you need on ebay for less then $40
Or just green sticker it.
Or just green sticker it.
5-90
NAXJA Forum User
- Location
- Hammerspace
CARB's site doesn't list stations down there?
Granted, I've been trying to convince those fools that, as far as I'm concerned, ALL stations are "Test Only" (I don't allow them to do repairs...) but they're not buying it. I'm getting tired of paying more for the smog check than I pay for tags...
Try this link...
http://159.145.15.175/StationList/StationList.aspx
5-90
Granted, I've been trying to convince those fools that, as far as I'm concerned, ALL stations are "Test Only" (I don't allow them to do repairs...) but they're not buying it. I'm getting tired of paying more for the smog check than I pay for tags...
Try this link...
http://159.145.15.175/StationList/StationList.aspx
5-90
- Location
- Hammertown, USA
Sometimes 5-90 you need to read between the HTML.
5-90
NAXJA Forum User
- Location
- Hammerspace
cal said:Sometimes 5-90 you need to read between the HTML.
Aw, gimme a break. I'm psychotic, not psychic...:wierd:
5-90
TheWarWagon
NAXJA Forum User
- Location
- Ft. Worth, TX
sintax said:
Does my vehicle qualify for a smog exemption?
Smog inspections are required unless your vehicle is:
- Hybrid
- 1975 year model or older
- Diesel powered
- Electric
- Natural gas powered and has a Gross Vehicle Weight rating of 14,001 lbs. or more.
- Motorcycle
- Trailer
FarmerMatt
NAXJA Forum User
- Location
- Down on the Farm
We've got 4 ranch trucks on propane & still have to smog them...??
MJR
NAXJA Forum User
- Location
- Costa Mesa, CA
cracker said:
Dude your cat ain't doing shit with those numbers.
Gerr
NAXJA Forum User
- Location
- River Drive Norco Ca 92860
agreed, prolly bashed it a few to many times
Clean Racing
NAXJA Forum User
- Location
- Bellingham, Wa
Why do ya need a plate on the buggy anyways?? Your cat is not doing anything but taking up space.. I would also throw an O2 in for good measure as well... Then make sure the thing is Hot when you take it to test.
RWKHausSupply
NAXJA Forum User
- Location
- yorba linda, Cali
Avery, how old / bad looking is the cat? Is it a stock replacment? If its not that "bashed" in and a stock replacment let me know if you want me to take it in to autozone for a warranty exchange. Got one there about 6 months ago and its a lifetime warranty... Only it has to be a stock replacment type with the 4bolt front flange?
- Location
- Williams AZ
Gotta disagree guys. The only failure is on NOx...A CAT is not the answer. And having it hot will only increase the NOx. Hot motor is to get rid of HC's which he is not high on.
Clean Racing
NAXJA Forum User
- Location
- Bellingham, Wa
JohnX said:
Care to explain?? He only failed NOX, and has no EGR, so I am curious?? Only reason I say cat- is that is the same readings I had two years ago on my renix, slamed a new cat in it - passed flying colors.. The only reason I say get it hot, is that most of the smog techs these days are not very bright.. Now let me guess your a smog tech huh?? Granted he could go a heat range colder on the plugs and probibly help it out..
RWKHausSupply
NAXJA Forum User
- Location
- yorba linda, Cali
All I can add is what I read..
Let's consider the things that can cause NO^sub x^ to increase to an abnormally high level. Oxides of nitrogen (NO^sub x^) are formed when the combustion chamber temperature exceeds 2500°F (the ignition point for compressed nitrogen). The engine must normally be under some kind of load before it develops such high combustion chamber temperatures.Many emissions systems rely on an EGR valve to lower combustion chamber temperatures. Adding a small amount of inert exhaust gas when tlie engine is under load lowers the temperature in tlie combustion chambers just enough to reduce the formation of NO^sub x^. I've always thought this mediod was similar to feeding manure to a horse. Automotive engineers must agree because many vehicles now manage to control NOx without the help of an EGR valve. The Jeep you're working on is one such vehicle.
But everything else must be working properly if the EGR valve crutch is removed. As you correctly surmised, combustion chamber deposits can artificially raise the compression ratio and encourage the formation of NO^sub x^. Overaclvanced ignition timing can also cause NO^sub x^ formation. Since the Jeep does not have an externally adjustable ignition system, we should be able to rule it out as a possible cause in this case. Jury-rigging the ignition in an attempt to retard the timing is not an acceptable solution.
Check with the owner to make sure the PCM hasn't been "chipped" or modified in some other way. One quick and dirty way to increase engine performance is to change the spark advance curve. This used to be accomplished by changing the advance springs in the distributor. Now it's done by changing the PCM's timing decisions. Too much advance at the wrong time, caused by an aftermarket chip modification, could be responsible for the excessive NOx problem.
A lean air/fuel mixture can also encourage NO^sub x^ formation. The lean mixture can be caused by insufficient fuel pressure or volume, or the engine management system may actually be commanding the mixture lean. This could occur if the PCM is receiving bogus information from an oxygen sensor that has a lazy response rate or has become biased rich. Your emissions readings didn't include an Oo reading, which would have been helpful in determining whether the engine is running rich or lean under load.
Be sure to consult Sam Bells article on lambda in this issue ("What Goes In..."). The lambda calculation is a great way to determine whether an engine is running rich or lean, without having to concern yourself with other influences.
Last of all, an engine that's running hotter than normal will encourage NO^sub x^ formation. A faulty thermostat or a clogged cooling system could be keeping the Jeep's operating temperature just shy of overheating. Adding a load pushes the combustion chamber temperature to the point where NO^sub x^ formation increases to an unhealthy level. The engine should be producing almost no NO^sub x^ at idle. If the NO^sub x^ reading is high at idle, run through the NO^sub x^-influencing factors I've listed until you find the cause.
Let's consider the things that can cause NO^sub x^ to increase to an abnormally high level. Oxides of nitrogen (NO^sub x^) are formed when the combustion chamber temperature exceeds 2500°F (the ignition point for compressed nitrogen). The engine must normally be under some kind of load before it develops such high combustion chamber temperatures.Many emissions systems rely on an EGR valve to lower combustion chamber temperatures. Adding a small amount of inert exhaust gas when tlie engine is under load lowers the temperature in tlie combustion chambers just enough to reduce the formation of NO^sub x^. I've always thought this mediod was similar to feeding manure to a horse. Automotive engineers must agree because many vehicles now manage to control NOx without the help of an EGR valve. The Jeep you're working on is one such vehicle.
But everything else must be working properly if the EGR valve crutch is removed. As you correctly surmised, combustion chamber deposits can artificially raise the compression ratio and encourage the formation of NO^sub x^. Overaclvanced ignition timing can also cause NO^sub x^ formation. Since the Jeep does not have an externally adjustable ignition system, we should be able to rule it out as a possible cause in this case. Jury-rigging the ignition in an attempt to retard the timing is not an acceptable solution.
Check with the owner to make sure the PCM hasn't been "chipped" or modified in some other way. One quick and dirty way to increase engine performance is to change the spark advance curve. This used to be accomplished by changing the advance springs in the distributor. Now it's done by changing the PCM's timing decisions. Too much advance at the wrong time, caused by an aftermarket chip modification, could be responsible for the excessive NOx problem.
A lean air/fuel mixture can also encourage NO^sub x^ formation. The lean mixture can be caused by insufficient fuel pressure or volume, or the engine management system may actually be commanding the mixture lean. This could occur if the PCM is receiving bogus information from an oxygen sensor that has a lazy response rate or has become biased rich. Your emissions readings didn't include an Oo reading, which would have been helpful in determining whether the engine is running rich or lean under load.
Be sure to consult Sam Bells article on lambda in this issue ("What Goes In..."). The lambda calculation is a great way to determine whether an engine is running rich or lean, without having to concern yourself with other influences.
Last of all, an engine that's running hotter than normal will encourage NO^sub x^ formation. A faulty thermostat or a clogged cooling system could be keeping the Jeep's operating temperature just shy of overheating. Adding a load pushes the combustion chamber temperature to the point where NO^sub x^ formation increases to an unhealthy level. The engine should be producing almost no NO^sub x^ at idle. If the NO^sub x^ reading is high at idle, run through the NO^sub x^-influencing factors I've listed until you find the cause.
- Location
- Williams AZ
Nope...Just a lowly mechanic. I was merely passing on info from a friend of mine who is a smog guy and has been for many years. I don't know what NOx is or how to raise or lower it. I only know what I'm told. I was told a cooler ENGINE creates less NOx and high humidity with low air temp also lowers it. A cooler CAT will not burn off the extra HC's, but HC's aren't the issue.Clean-RC said:
MJR
NAXJA Forum User
- Location
- Costa Mesa, CA
Clean-RC said:
That is the PROBLEM.
