Failed Emission Test. HELP!!!
Thread Starter
Instructor
Joined: Feb 2006
Posts: 233
Likes: 1
From: Port Washington Wi.
Failed Emission Test. HELP!!!
Just failed my emissions test here in the great state of Wisconsin. Two years ago when I bought my 2000 coupe I had to have it tested and it passed with flying colors. Yesterday I took it in and everything appeared fine. The technician could not get the little device that they plug into the diagnostice port to read so they had to do the running test on the dyno. The tech said I failed on all three gases. When I got back in to drive away the check engine light was on. When I got home the codes were all communication codes that were history and not active. I reset them and the check engine light went away.
My car has been slightly modified with a larger intake, headers, hi flow cats and B&B route 66 exhaust. I think it may have been tuned also. This past winter the battery died and I had to take it out to recharge it.
I guess my questions are.
Could the fact that it threw some codes during the test cause it to fail?
Now that the codes are gone should it pass the test?
Did the dead battery cause the computer/tune to get goofed up?
Any help would be appreciated.
Thanks as always
My car has been slightly modified with a larger intake, headers, hi flow cats and B&B route 66 exhaust. I think it may have been tuned also. This past winter the battery died and I had to take it out to recharge it.
I guess my questions are.
Could the fact that it threw some codes during the test cause it to fail?
Now that the codes are gone should it pass the test?
Did the dead battery cause the computer/tune to get goofed up?
Any help would be appreciated.
Thanks as always
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
No surprise you failed the sniff test with aftermarket cats. Not sure why you didn't pass the plug in test, unless he was busting your chops. What does your re-test consist of, do you know? Something like Autotap will tell you if you will pass the test ahead of time.
See if the check engine light comes back on and occasionally check for further communications codes. That could have been his issue with not being able to hook up.
See if the check engine light comes back on and occasionally check for further communications codes. That could have been his issue with not being able to hook up.
Burning Brakes
Joined: Jul 2007
Posts: 881
Likes: 2
From: hill billy hell
Could the fact that it threw some codes during the test cause it to fail?
When I got home the codes were all communication codes
Did the dead battery cause the computer/tune to get goofed up?
Now that the codes are gone should it pass the test?
Are you required to have a visual inspection?
Are you required to get check with a sniffer?
Some states just require hooking up to your OBD II connector and checking for emission related codes along with seeing if your system has performed and passed certain testing phases. Hard to believe a loose or bad gas cap can make you fail
Last edited by jirasvet; Sep 12, 2007 at 07:42 PM.
Le Mans Master
Joined: Aug 2003
Posts: 9,298
Likes: 4
From: American Canyon Lethal Injection
That is one of the "tricks" let the cats get good and hot. It could be the tune you have also. (It was with mine) After a re-tune to pass smog I was ok, after the sniffer test..the tner brought it back to my tune.
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Le Mans Master
Joined: Aug 2003
Posts: 9,298
Likes: 4
From: American Canyon Lethal Injection
Just failed my emissions test here in the great state of Wisconsin. Two years ago when I bought my 2000 coupe I had to have it tested and it passed with flying colors. Yesterday I took it in and everything appeared fine. The technician could not get the little device that they plug into the diagnostice port to read so they had to do the running test on the dyno. The tech said I failed on all three gases. When I got back in to drive away the check engine light was on. When I got home the codes were all communication codes that were history and not active. I reset them and the check engine light went away.
My car has been slightly modified with a larger intake, headers, hi flow cats and B&B route 66 exhaust. I think it may have been tuned also. This past winter the battery died and I had to take it out to recharge it.
I guess my questions are.
Could the fact that it threw some codes during the test cause it to fail?
Now that the codes are gone should it pass the test?
Did the dead battery cause the computer/tune to get goofed up?
Any help would be appreciated.
Thanks as always
My car has been slightly modified with a larger intake, headers, hi flow cats and B&B route 66 exhaust. I think it may have been tuned also. This past winter the battery died and I had to take it out to recharge it.
I guess my questions are.
Could the fact that it threw some codes during the test cause it to fail?
Now that the codes are gone should it pass the test?
Did the dead battery cause the computer/tune to get goofed up?
Any help would be appreciated.
Thanks as always
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
If you have any CEL lights and clear them before the test, you will have NOT READY flags set and fail the test. It takes driving cycles to clear the not ready flags. What DTCs are you having to get CEL lights?
Examine your OBD-II connection under the driver side dash. Take your car to Autozone and see if their OBD-II scanner will fit correctly in the OBD-II port. Sounds like your emissions station guy was a BOOB!
Examine your OBD-II connection under the driver side dash. Take your car to Autozone and see if their OBD-II scanner will fit correctly in the OBD-II port. Sounds like your emissions station guy was a BOOB!
Thread Starter
Instructor
Joined: Feb 2006
Posts: 233
Likes: 1
From: Port Washington Wi.
If you have any CEL lights and clear them before the test, you will have NOT READY flags set and fail the test. It takes driving cycles to clear the not ready flags. What DTCs are you having to get CEL lights?
Examine your OBD-II connection under the driver side dash. Take your car to Autozone and see if their OBD-II scanner will fit correctly in the OBD-II port. Sounds like your emissions station guy was a BOOB!
Examine your OBD-II connection under the driver side dash. Take your car to Autozone and see if their OBD-II scanner will fit correctly in the OBD-II port. Sounds like your emissions station guy was a BOOB!
Racer
Joined: Aug 2005
Posts: 361
Likes: 1
From: Montara Ca
I just went through this problem here in CA. Two years ago after my last smog test I installed a Vortex CAI, LS6 intake and 28lb injectors, LG street long tubes, high flow cats and Z06 Ti’s on my 99 coupe and DID NOT get a tune. Car now has 160K on the OD, went for my smog test a couple weeks ago and passed the visual (tech overlooked the LT and CAI) but failed the sniffer for HC at 750 rpm, (Max allowed is 100ppm, I was blowing around 130ppm). All was good at 2500 rpm. Went home and put in new plugs and fresh oil, made sure the catch can was clean then went back for retest. Car was now blowing >200ppm HC at 750 rpm. I talked to our local tuner here in the Bay Area and he said bring it in for a tune. Rick’s the man, car base lined at 328 rwt and 308 rwhp , after the tune, 344 rwt & 324 rwhp. So I went back to my smog guy and blew a clean 36ppm HC at 750 and 31ppm at 2500rpm. Moral of the story… Get a good tune.
Advanced
Joined: Jun 2007
Posts: 60
Likes: 0
From: Ontario
There are two things I do before taking a car in for emissions testing, if I suspect it might fail:
1. I only have 1/4 tank of gas in it or less and add around a pint of methal hydrate (gas line antifreeze) to the gas. Check and make sure this isn't going to screw up your injectors or anything else in the fuel loop first.
2. Take it for a good run to heat up the cats. Then straight into the garage for the test, hopefully the get it in before they cool off.
Supposedly the methal hydrate burns cleaner and emits less emissions.
A fairly common practice around where I am in Ontario.
1. I only have 1/4 tank of gas in it or less and add around a pint of methal hydrate (gas line antifreeze) to the gas. Check and make sure this isn't going to screw up your injectors or anything else in the fuel loop first.
2. Take it for a good run to heat up the cats. Then straight into the garage for the test, hopefully the get it in before they cool off.
Supposedly the methal hydrate burns cleaner and emits less emissions.
A fairly common practice around where I am in Ontario.
Last edited by ukonjack; Sep 16, 2007 at 07:04 AM. Reason: changed to hydrate
Pro
Joined: Jun 2005
Posts: 593
Likes: 1
Just failed my emissions test here in the great state of Wisconsin. Two years ago when I bought my 2000 coupe I had to have it tested and it passed with flying colors. Yesterday I took it in and everything appeared fine. The technician could not get the little device that they plug into the diagnostice port to read so they had to do the running test on the dyno. The tech said I failed on all three gases. When I got back in to drive away the check engine light was on. When I got home the codes were all communication codes that were history and not active. I reset them and the check engine light went away.
My car has been slightly modified with a larger intake, headers, hi flow cats and B&B route 66 exhaust. I think it may have been tuned also. This past winter the battery died and I had to take it out to recharge it.
I guess my questions are.
Could the fact that it threw some codes during the test cause it to fail?
Now that the codes are gone should it pass the test?
Did the dead battery cause the computer/tune to get goofed up?
Any help would be appreciated.
Thanks as always
My car has been slightly modified with a larger intake, headers, hi flow cats and B&B route 66 exhaust. I think it may have been tuned also. This past winter the battery died and I had to take it out to recharge it.
I guess my questions are.
Could the fact that it threw some codes during the test cause it to fail?
Now that the codes are gone should it pass the test?
Did the dead battery cause the computer/tune to get goofed up?
Any help would be appreciated.
Thanks as always
Not the tech's fault as the law states if they cannot do the I/M test then car fails and must then do the I/M 240 15/25 MPH threadmill for tailpipe readings
Doing those tests could trigger misfires or AFR issue causing the error but if SES is on for any reason and scanner cannot be used to see what is failing car fails.
Clearing error code auto clears all internal smog tests in the PCM and it can take several drive cycles to get them back into a passed state.
Just doing one drive will not get all tests back into a complete state.
You cleared the codes but caused all smog tests to default back to a non complete state
If not sure if car will pass is do a smog PREtest first so if it fails it is not recorded to state's database as failed which can cause state to force more often testing for that car.
Last edited by boosted_z06; Sep 15, 2007 at 09:54 PM.
Drifting
Joined: Jun 2002
Posts: 1,945
Likes: 41
From: Corinth TX
Since you have cleared all of your codes, run the car for a nice 45-50 mile trip to hopefully take care of the drive cycle diagnostics. If no codes have come back, then take the car and get it inspected. The cats should be plenty hot by this time. I have had 2 cars that failed the emissions tests and both times were because my wife took the car directly over and had it tested. I can't complain though because I had worked all night long and she was doing it out of kindness.
Goodluck on the retest and keep everyone up to date on how it goes.
PS: Alot of people have ran Seafoam after failing and passed the test afterwards.
Goodluck on the retest and keep everyone up to date on how it goes. PS: Alot of people have ran Seafoam after failing and passed the test afterwards.
Thread Starter
Instructor
Joined: Feb 2006
Posts: 233
Likes: 1
From: Port Washington Wi.
Thanks for all the input. I took it for a good run yesterday putting about seventy five miles on it. Ran up to Road America in Elkhart Lake and watched practive and qualifying for the vintage weekend. It was great to see all the late sixty early seventies Camaros, Vettes, and Mustangs racing. There was a pit with two 69 camaros a C5 vette and a ninties camaro. One of the 69's was black number 0. Did that thing haul the mail down the front stretch. What a blast.
Hope to take it up and test again this week. Will let you know what happens.
Hope to take it up and test again this week. Will let you know what happens.
Thread Starter
Instructor
Joined: Feb 2006
Posts: 233
Likes: 1
From: Port Washington Wi.
If not sure if car will pass is do a smog PREtest first so if it fails it is not recorded to state's database as failed which can cause state to force more often testing for that car.[/QUOTE]
Do they do the "smog PREtest" right at the testing station?
Do they do the "smog PREtest" right at the testing station?
Drifting
Joined: May 2004
Posts: 1,822
Likes: 2
From: San Clemente CA
As others have said, first things first. The tech should've warmed the cats for at least a couple of minutes with varying loads on the engine before he ever inserted the sniffer. My old 4Runner nearly failed a few years back when the tech at the local gas station failed to do this. Not knowing any better at the time, I was pretty worried the next time I went to get smogged. I was required to go to a Test Only station for bad boyz and gross polluters. The tech there warmed everything up and I passed by a country mile!