Failed emissions test
Thread Starter
Le Mans Master
Joined: Dec 2001
Posts: 5,705
Likes: 548
From: St. Peters MO
C7 of Year Finalist (stock) 2019
2018 C7 of Year Finalist
Failed emissions test
My 82 failed a mandatory emissions test today. The technician showed me the readout and pointed out that I had barely failed.
They test three areas. I passed two and failed the HC (hydrocarbons) test. I had to achieve a standard of no more than 0.8000 grams per mile. I got a 0.8692 which caused me to fail the test.
The technician said if I used some octane boost and some 93 octane gas he felt it may pass on the retest since it was so close on the initial test.
I have no idea if his advice is sound or not. Anyone out there have any suggestions before I take the retest?
They test three areas. I passed two and failed the HC (hydrocarbons) test. I had to achieve a standard of no more than 0.8000 grams per mile. I got a 0.8692 which caused me to fail the test.
The technician said if I used some octane boost and some 93 octane gas he felt it may pass on the retest since it was so close on the initial test.
I have no idea if his advice is sound or not. Anyone out there have any suggestions before I take the retest?
Safety Car
Joined: Dec 2004
Posts: 4,071
Likes: 0
From: San Diego CA
Originally Posted by 682XLR8
If you are certain the car is tuned and the rest of the smog equipment is working, I'd bet the converter was bad
Before you go for a retest get the catalytic convertor as hot as possible by driving on the highway in 3rd for like 20 minutes or so. Then get it tested immediately after you get it piping hot. That should get the HCs lower.
Melting Slicks
Joined: Jan 2003
Posts: 2,817
Likes: 21
From: Somerset, NJ
If you want to pass your emissions test go and get yourself a bottle of a product called Fuelon. As long as you are not burning oil where your car smokes this stuff will get you through inspection. I know I have used it plenty of times to get through N.J. Inspection and the stuff works. Works so well that you will not believe the reading you will achieve once going through inspection after using the product. Some readings were down to almost zero. Anyway here is the link to Fuelons website: http://www.fuelon.com/fuelonpower.html
Last edited by ffas23; Jul 30, 2006 at 01:23 AM.
Advanced
Joined: May 2006
Posts: 61
Likes: 0
From: NORWICH UNITED KINGDOM
Hydrocarbons is unburnt fuel coming through the exhaust. In the uk this test is done at idle. You could tweek the idle screws for the test and put them back when you drive away. As mentioned by other members there is also a product in uk which you can add to fuel and this will give a temporary lower figure. I had a diesel car once which failed same test. I filled the fuel filter with neat stuff just before test and it sailed through test.
Le Mans Master
Joined: Nov 1999
Posts: 8,511
Likes: 3
From: Memphis, Tn
My guess is a new O2 sensor is needed. You have the CrossFire, whick is sorta like fuel injection. The computer looks at the O2 reading and adjust accordingly to provide enough air to burn all the fuel. With a high CO reading, you aren't burning all the fuel. In other words, the engine is running rich. Also try new air filter. And always warm up the cat converter real good before the test. You do that with several WOT runs 
.
.
Racer
Joined: Mar 2005
Posts: 445
Likes: 0
From: SAN DIEGO(SANTEE) CA.
Originally Posted by 2k2C5
My 82 failed a mandatory emissions test today. The technician showed me the readout and pointed out that I had barely failed.
They test three areas. I passed two and failed the HC (hydrocarbons) test. I had to achieve a standard of no more than 0.8000 grams per mile. I got a 0.8692 which caused me to fail the test.
The technician said if I used some octane boost and some 93 octane gas he felt it may pass on the retest since it was so close on the initial test.
I have no idea if his advice is sound or not. Anyone out there have any suggestions before I take the retest?
They test three areas. I passed two and failed the HC (hydrocarbons) test. I had to achieve a standard of no more than 0.8000 grams per mile. I got a 0.8692 which caused me to fail the test.
The technician said if I used some octane boost and some 93 octane gas he felt it may pass on the retest since it was so close on the initial test.
I have no idea if his advice is sound or not. Anyone out there have any suggestions before I take the retest?
Man was I
Drifting
Joined: Nov 2005
Posts: 1,795
Likes: 1
everyone has an opinion so here's mine.
whens the last time you really jumped on it hard?
sometimes when you pussyfoot around they will carbon up
causing a slightly higher reading like you received on your test.
take it out on the highway and when its clear stomp that
sucker to the floor and blow the carbon out.
now if your a lead foot and stand on it from time to time disregard
this post
whens the last time you really jumped on it hard?
sometimes when you pussyfoot around they will carbon up
causing a slightly higher reading like you received on your test.
take it out on the highway and when its clear stomp that
sucker to the floor and blow the carbon out.
now if your a lead foot and stand on it from time to time disregard
this post
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Thread Starter
Le Mans Master
Joined: Dec 2001
Posts: 5,705
Likes: 548
From: St. Peters MO
C7 of Year Finalist (stock) 2019
2018 C7 of Year Finalist
Originally Posted by 1Z87L8
everyone has an opinion so here's mine.
whens the last time you really jumped on it hard?
sometimes when you pussyfoot around they will carbon up
causing a slightly higher reading like you received on your test.
take it out on the highway and when its clear stomp that
sucker to the floor and blow the carbon out.
now if your a lead foot and stand on it from time to time disregard
this post
whens the last time you really jumped on it hard?
sometimes when you pussyfoot around they will carbon up
causing a slightly higher reading like you received on your test.
take it out on the highway and when its clear stomp that
sucker to the floor and blow the carbon out.
now if your a lead foot and stand on it from time to time disregard
this post
I am also going to try some octane boost. Hopefully, it will pass this time around. Thanks to everyone for their replies.
Burning Brakes
Joined: Jun 2005
Posts: 769
Likes: 0
From: NorCal 71 Lt-1
Originally Posted by 682XLR8
If you are certain the car is tuned and the rest of the smog equipment is working, I'd bet the converter was bad
with 682XLR8. if your cat is original it may not be doing it's job efficiently and needs to be replaced. was the co or nox readings borderline / high even though those gases passed? i would look for a long term solution if you have biannual inspections.
Thread Starter
Le Mans Master
Joined: Dec 2001
Posts: 5,705
Likes: 548
From: St. Peters MO
C7 of Year Finalist (stock) 2019
2018 C7 of Year Finalist
Originally Posted by wnjlt1
i have to with 682XLR8. if your cat is original it may not be doing it's job efficiently and needs to be replaced. was the co or nox readings borderline / high even though those gases passed? i would look for a long term solution if you have biannual inspections.
with 682XLR8. if your cat is original it may not be doing it's job efficiently and needs to be replaced. was the co or nox readings borderline / high even though those gases passed? i would look for a long term solution if you have biannual inspections.The CO reading was, Standard: 30.000gpm, Test reading: 10.1656gpm, and NOx was, Standard: 2.000gpm, Test reading: 1.5641gpm.
The cat was replaced at some point but not by me. The real frustrating thing is in 2007 the emissions testing in Missouri is changing to a OBD II test. All vehicles 1995 and older will be exempt from emission testing. Plus in 2007 the 82 will be 25 years old and I can get historic license plates that require no testing either. So I am stuck with having to get it to pass this one last time.
If all else fails I can get an exemption but that requires I spend a minimum of $450 in an attempt to improve the test reading. Thing is if I improve the reading just a little I can pass the test.
I'll report back what happens when I get the retest.
Race Director
Joined: Feb 2006
Posts: 13,138
Likes: 0
From: Inside the woods living my passion
St. Jude Donor '07-'08
Have you done a major tune up? cap, rotor ,plugs wires ? If you bairly failed, and at least do a cap ,rotor, plugs( if not done) and some 92 oct gas and give the car a good ole hwy run you should be good to go.
Last edited by C3Racing; Jul 30, 2006 at 07:58 PM.
Race Director
Joined: Sep 1999
Posts: 11,360
Likes: 382
From: Plano TX
A trick to lower HC is to do an oil change. May sound odd, but what happens is that some fuel goes into the oil and then slowly gets reintoduced into the chambers elevating HC. After an oil change the HC levels drop a bit.
Instructor
Joined: Jun 2006
Posts: 146
Likes: 5
From: North Brunswick New Jersey
Had same thing happen here in NJ. I poured about a quart of methanol in the tank and, after failing again, found I had a vacuum leak. After the leak was fixed, the HC reading with the methanol was way below the threshold. Don't forget to adjust the idle mixture screws and make sure the choke is fully opening.
Advanced
Joined: Jun 2006
Posts: 58
Likes: 0
From: Leesburg Virginia
Very Similar
My situation was very similar for my 82 CE. I ended up needing a catalytic converter, O2 sensor, and a good sea foaming helped.
if you are getting the cat converter replaced, it does need break in time before you test, so run it about 20 minutes before the test.
Next year it will be an official antique, so no more emissions inspection.
if you are getting the cat converter replaced, it does need break in time before you test, so run it about 20 minutes before the test.
Next year it will be an official antique, so no more emissions inspection.
Instructor
Joined: Jul 2006
Posts: 159
Likes: 0
cant you buy inspection stickers for like $100 and not even have to test it, its something like that but thats here in texas we had to do it on a couple of trucks at my work. i dunno tho, if you cant get it to pass with the octane booster and all that mess then that may be something for you to look at
Drifting
Joined: Jun 2005
Posts: 1,523
Likes: 1
From: grand prairie texas
Try an oxygen sensor if your car has one. My old car failed texas emissions and I put a cat on it and egr valve also a throttle position sensor and it failed again. A buddy told me to put an oxygen sensor on my car and it passed with flying colors. You would really be surprised about how much that sensor will help emissions.
Thread Starter
Le Mans Master
Joined: Dec 2001
Posts: 5,705
Likes: 548
From: St. Peters MO
C7 of Year Finalist (stock) 2019
2018 C7 of Year Finalist
Took the 82 back for a retest today and IT PASSED!!!
I put in a bottle of octane boost and a bottle of Guaranteed to Pass Emissions Formula (yeah, thats what its called) and then filled the half empty tank with BP 93 octane. I took a 30 mile drive on I-70 with a bunch of hard accelleration runs to warm it up good and blow out the carbon and then went straight to the testing facility.
The technician was impressed that it did so well. The HC went from a failing 0.8692 (could not be more than 0.8000) to 0.6636. The CO and NOx readings went down as well.
So I am happy. I won't ever have to have it tested again and I can get my license plates renewed.
Thanks to everyone for their help. I appreciate it.
I put in a bottle of octane boost and a bottle of Guaranteed to Pass Emissions Formula (yeah, thats what its called) and then filled the half empty tank with BP 93 octane. I took a 30 mile drive on I-70 with a bunch of hard accelleration runs to warm it up good and blow out the carbon and then went straight to the testing facility.
The technician was impressed that it did so well. The HC went from a failing 0.8692 (could not be more than 0.8000) to 0.6636. The CO and NOx readings went down as well.
So I am happy. I won't ever have to have it tested again and I can get my license plates renewed.
Thanks to everyone for their help. I appreciate it.
All it needed was an Italian tuneup!