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Failed Emissions 3 times HELP!

Gator4x said:
freakin money. I wanted to take a sledge to the test techs when they kept tellin my the NOX went up again. I know it's not their fault, but gosh darn this emissions stuff is agravating!

i agree with you completely. i think its a ploy to get older cars off the road and get people into newer ones. i will forever try my best to beat the emissions system for as long as i own a running vehicle. if it does not pass i wil do everything i can in my power to make it pass without having to pay a mechanic. i hate nothing more than to pay someone to do a repair. (thats how i justify buying new tools to my wife: O )

but when it comes to paying somoene off i don't know anyone who would do that but have known people who have gotten caught and put out of business. i would rather deal with my issues and see if they work so i know in the future.

i went to partsamerica.com looked up the o2 sensor, brought the printout to kragen and they gave me a lower price. not bad. and the swap took me 10 minutes max, plug and play.

you'll pass, i bet its an o2 sensor. btw, when was the cat replaced last? mine was 2 years ago when i bought my POS.
 
POS-as far as I know it's the original cat and original O2. no idea.

I think I'm going to pick up the Chapion truck plugs (I had installed the reglar Champions), new O2 and new cat tonight. Put all the stuff on and see how she does.

I'm tempted to just replace the O2 sensor and see what happens but I don't want to have to keep paying the $15 fee. Hmm, that would tell me which component finally fixed the problem though...decisions, decisions...

I'll try to go for a re-test tomorrow night. That should be cool. Hopefully she runs real guuuuuuuud! :D

later,
Nick
 
A partially plugged cat will increase back pressure and raise cylinder temps. The quiet exhaust is also a tell, does it also have a hissing type sound coming from the tailpipe?

The O2 sensor and cat should be the fix, you'll probably pick up some noticeable power too:D
 
Picked up a Cat and O2 sensor last night. I'll be putting them on Friday night. Might have the fuel injectors cleaned by the dealership this afternoon. Picking up some Champion truck plugs tonight as well. I'm thinking all this stuff should clear up my problems...

Kuasimodem-I'm really thinking the cat is plugged up. I'm anxious to cut the sucker off and check it out!!!
 
I put a new cat on my 93 last year and all the emissions numbers went WAY down. I was still passing with the old one, but it was rattling pretty good at stop lights after it got good and hot. I bet you'll pass this time. Don't forget to get her warmed up good before going in...
 
Find someone who carries BG products (most dealers and NAPA do) and get THE cleaner 44K. I went from 14 mpg to 20 mpg in the same driving conditions first try in my Comanche (disconnected EGR, gutted CAT and I passed E test with flying colors!) There is also a high altitude and low altitude programming that the dealer can do to recurve (lowering engine timing drops NOx) If the dist isn't set right, the sensors can mismatch just enough to mess you up.
I've had new cats pump the NOx higher than no cat at all.
 
Gator4x said:
POS-as far as I know it's the original cat and original O2. no idea.

I think I'm going to pick up the Chapion truck plugs (I had installed the reglar Champions), new O2 and new cat tonight. Put all the stuff on and see how she does.

I'm tempted to just replace the O2 sensor and see what happens but I don't want to have to keep paying the $15 fee. Hmm, that would tell me which component finally fixed the problem though...decisions, decisions...

I'll try to go for a re-test tomorrow night. That should be cool. Hopefully she runs real guuuuuuuud! :D

later,
Nick

Your complainiang about a $15 retest fee, :sure: , try a $40-50 Retest fee.

Also I feel you wasting money on the truck plugs.
 
langer1 said:
Can a Dealer legally sell a car that don't pass emissions? In Ohio they can't it must be smogged first in counties where testing is required.

Sure! Even your neighbors here in Nazi-run Pennsylvania buy and sell cars freely. Sure, good inspection stickers (for safety and emissions) are a "selling point" that will draw more $$$, but there's no requirement for a test/inspection before a sale can happen... the stickers can even be EXPIRED.

It's all up to the new owner to figure it out.

At any rate.... at 150k, I'd point fingers at the cat myself... and O2 sensors are more of a "wear" item these days.... I'd replace them both.

Den
 
At least here in CA, the SELLER is responsible for making the vehicle pass the Smog Nazis (but I still get tired of explaining that all of my XJ's are PRE-OBD, and therefore do NOT have a bulb in the MIL, and no, I did not remove it just to be difficult! With five rigs, I think I go through that every six months or so, you'd think they'd learn...)

Try replacing your cat (they're usually only good for about ten years anyhow - a "universal" should work for you, and you can have the bung for the downstream HEGO sensor welded into a pipe if you need it) and the upstream HEGO sensor (which provides feedback for fuel metering) - that's what I'd do first. Go with Bosch or ACDelco for the HEGO sensor, and don't get a "universal" - I don't trust them.

A "high NOx" failure usually traces back to lean AFR (failed upstream HEGO sensor) or a failed/plugged catalytic converter. Plugged injectors are also possible, but somewhat rarer (due to the detergents in gasoline, and the Jeeper having a bit more interest in maintaining his vehicle than the average driver.)

If you have access to an ultrasonic jewelry cleaner, you can probably save a few bucks cleaning your injectors yourself, and then just get in the habit of running acetone (~2oz./10 gallons gasoline, or ~4-5oz/tankful) every couple months or so for a maintenance cleaning. It's cheaper than "injector cleaner," and essentially the same thing anyhow.

5-90
 
5-90 said:
At least here in CA, the SELLER is responsible for making the vehicle pass the Smog Nazis


That would create an entirely different social situation! Heck, it's Standard Operating Procedure amongst the poorer folks here... to SELL you car if it doesn't pass emissions, and buy another car with good stickers on it!!

Happens everyday.

Then again, we also have a rule that says you get a "waiver" once you've proven that you've invested $500 into repairing the emissions issue, and it still failed. So the max that fixes "should" cost is $500/year.

Cat + O2 + labor = pass... regardless of the numbers

Den
 
Pre-96 = no OBD plug-in... Thus, your exhaust output it tested... Thus, simply run the gas tank down to about 1/8 and add about 10 bottles of gas-line anti-freeze, which will alter the output sufficiently...and probably much more than that...to pass comfortably... Try it...:)
 
My part of PA doesn't do emissions testing, YET but I bought my J10 from a part of PA that does. Thankfully in PA you can get a waiver for emissions if you only drive a vehicle less that a given mileage per year, 5K IIRC.

In New York state they do the OBD test, non-OBD vehicles are a visual inspection to verify everything is still there, if so you pass. In New York City they do the dino/sniffer tests. Also in the state of NY dealers are responsible for ensuring all vehicles will pass safety/emissions before sale, not so sure about private sales.
 
yeah WI is kinda goofy with their laws. A dealer is required to do a safety inspection before selling a vehicle, and is required to tell the purchaser about the items that failed/passed, but no more detail than that. If it says "4wd sysytem-failed" you don't know exactly what the problem is.

And they don't have to fix it either...

I bought my truck in Illnoise and my truck didn't even get a safety inspection. Plus it was from a super sketchy used car lot. Not one a them fancy "Pre-owned" lots. hahaha

So this weekend I put on the new cat, new O2 and new truck plugs. Changed the diff fluid. She is running GREAT now. Much more power and a louder exhaust note. It was so freaking quiet before because there was basically no fuel goin for a good loud "bang."

Cat wasn't plugged up and may have passed, but it's been roasted scalding hot for lord only knows how many thousands of miles, so it was worth the $150 for me to just swap it out.

Went to get tested, and after you fail three times they do an inspection to make sure everything is there.

Of course as soon as they saw my Rusty's intake they failed me. So I get to swap the stock airbox back on and head back again...

I know it'll pass this time, though. I just KNOW it!!! hahaha
 
Gator4x said:
yeah WI is kinda goofy with their laws. A dealer is required to do a safety inspection before selling a vehicle, and is required to tell the purchaser about the items that failed/passed, but no more detail than that. If it says "4wd sysytem-failed" you don't know exactly what the problem is.

And they don't have to fix it either...

I bought my truck in Illnoise and my truck didn't even get a safety inspection. Plus it was from a super sketchy used car lot. Not one a them fancy "Pre-owned" lots. hahaha

So this weekend I put on the new cat, new O2 and new truck plugs. Changed the diff fluid. She is running GREAT now. Much more power and a louder exhaust note. It was so freaking quiet before because there was basically no fuel goin for a good loud "bang."

Cat wasn't plugged up and may have passed, but it's been roasted scalding hot for lord only knows how many thousands of miles, so it was worth the $150 for me to just swap it out.

Went to get tested, and after you fail three times they do an inspection to make sure everything is there.

Of course as soon as they saw my Rusty's intake they failed me. So I get to swap the stock airbox back on and head back again...

I know it'll pass this time, though. I just KNOW it!!! hahaha

Point is if it don't pass you don't buy, but if they don't disclose that information, their in trouble.
 
I found so few AX15 4x4 4.0L's (AX15 being the limiter here) that I wasn't terribly picky about what I bought. The big thing was as little rust a possible and runs half decent. I checked the thing out pretty thoroughly, but you never catch everything...I tend not to catch the really expensive crap too well...sheesh. But all told, for about $5k I'll have a well built good running clean rig...
 
OK well,
GOOD NEWS!!! She PASSED! I knew she sounded like she was runnin right, and the test confirmed it. I want to outline what I saw and did so anyone else who runs into the same problems can learn from my experience...

So here is the summary:
Originally failed in HC's and NOX

Found problems:
-Exhaust leak @ exhaust manifold to mid-pipe connection [replaced header so I wouldn't have to screw with it later] $130 through APN
-MANY vacuum leaks. Cracked/pulled off hoses. [All fixed.] $cheap/free
-LOTS of carbony/oily buildup in intake pipe, intake manifold, CCV system and intake ports. [All disassembled and cleaned until spotless with brushes/air/picks/carb cleaner/brake cleaner.] $cheap/free
-Fuel Pressure regulator was found not to be holding pressure during accel/decel events. [FPR replaced.] $90
-Electric Auxiliary fan wasn't working ever, at all. [found blown wrong amperage fuse-replaced, works great.] $.50

Other than these things general maintenance items were performed including:
-Radiator flush and refill, replaced thermostat with a 180* unit because Jeep was heating up badly, quickly. $35
-Oil, lube & oil & air filter change. Lubed EVERYTHING! $30
-Changed F&R diff, manual tranny, and transfercase fluids to Mobil1. $Don't wanna add this up...
-New front u-joints $too much...
-New motor mounts $20
-New clutch $740
-Rusty's tailpipe and Flowmaster 40 muffler installed. $130
-New Champion TRUCK PLUGS. Not the .37c/ea regular garbage $18
-Ran 2 bottles (on seperate tanks!) of Lucas fuel system cleaner through the gas.

These next few items though are what really made the difference. I kept failing with high NOx, which is caused by high cylinder temps. My plugs indicated that I was running very lean which went along with the high cylinder temps.

2 things commonly cause high NOx-Clogged injectors and a bad O2 sensor. Catalytic converters are not supposed to go bad on their own!!! A cat going bad is a symptom of another problem. Cat's like to go bad from fuel getting dumped on them (burns 'em up), and getting too hottt (burns 'em up :D). The more I tested and the more I fixed, the higher my NOx got. I finally had a couple other folks on here let me know that when their O2 was bad their NOx kept going up and up.

Another strange symptom of running lean was that the truck was really really quiet. Even with an FM 40...thought is was the cat all plugged up, but it wasn't. O2 was bad and there just wasn't any fuel going in so the bang wasn't loud...

I figured that since the truck had been running poorly for an indeterminable amount of time, that while replacing the O2 I should replace the cat as well.

So I replaced:
-Catalytic converter with direct fit type (universal type at Napa was TINY!) $150
-New Bosch O2 sensor. $60

Fired it up and I had a nice rumble back. The new O2 finally allowed the truck to get the right amount of fuel in. Passed even before the end of the driving cycle. Couldn't print out my pollutant levels cause they were too low to register on their system.

I see a lot of people having overheating problems on their trucks, and a lot of folks doing whatever they can to get around emissions. Frankly, I'm glad I had an emissions test to force me to get the truck running the best it can. It is running nice and cool now and I have yet to overheat it despite trying.

Thanks to all the knowledgable folks on here who helped me out. Ya'll are A-OK! :D

later,
Nick
 
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