Damned emission inspection
Thread Starter
Drifting
Joined: Dec 2003
Posts: 1,344
Likes: 0
From: Conyers Ga
Damned emission inspection
Well it finally happened.......My 88 failed the CO portion of the test.
Any ideas on where to start looking? The guy said check for a vacum leak which I did but found none. My last code was for the burn off relay on the MAF sensor which I cleared and chalked up to an intermittent.
Any ideas on where to start looking? The guy said check for a vacum leak which I did but found none. My last code was for the burn off relay on the MAF sensor which I cleared and chalked up to an intermittent.
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
run the snot out of it. make sure the EGR ports are clear.
also, when was the last tune up?
Take the car there when warm, and add a can of smog check, or similar product, through the engine.
also, when was the last tune up?
Take the car there when warm, and add a can of smog check, or similar product, through the engine.
Thread Starter
Drifting
Joined: Dec 2003
Posts: 1,344
Likes: 0
From: Conyers Ga
The tune up was in the last year. I usually do "drive the snot out of it" before the test but this time as was going past them and saw no line so I swung in. I know the year before last my mechanic took it and told the guy to leave the clamshell CLOSED. It passed just fine with no repairs of any sort.
Le Mans Master
Joined: Nov 2002
Posts: 7,080
Likes: 0
From: Corvette valley Georgia
St. Jude Donor '06
Len do you have the stock thermostat in it and how is the condition of the throttle valve bushing? Those are what I would look at, also how old are the injectors and have they been cleaned?
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Thread Starter
Drifting
Joined: Dec 2003
Posts: 1,344
Likes: 0
From: Conyers Ga
Hey Les,
Stock t'stat.......TV bushing? I'll have to look. The injectors are original but I run a can of cleaner about every 4 months or so. I did the carb cleaner vacum leak check but didn't find any.
What does unplugging the EST do?
Le Mans Master
Joined: Nov 2002
Posts: 7,080
Likes: 0
From: Corvette valley Georgia
St. Jude Donor '06
Also the injectors will be just flat out worn out and the spray pattern may not be opitmal.
If the engine has to be "hot" to pass it still sound as the injectors may not be as good as it can be.
Back in LA I changed out my injectors and my co was reduced to the point that my Nox was almost too high!!
How was the nox reading by the way? if it was alittle low I would suspect the injectors
Thread Starter
Drifting
Joined: Dec 2003
Posts: 1,344
Likes: 0
From: Conyers Ga
HC/ppm 065 allowed: 152 passed
CO% 1.57 allowed 0.97 failed
NO/ppm: 0477 allowed: 1082 passed
CO+CO2% 15.5 allowed 6.0 min
I have noticed the car running cooler but attributed it to the cold snap we had last week. I had made a run to the store, came home and went back out to the inspection so it's possible I didn't let it get hot enough.
My CO reading last year was 0.75
Headed to my shop next week.
CO% 1.57 allowed 0.97 failed
NO/ppm: 0477 allowed: 1082 passed
CO+CO2% 15.5 allowed 6.0 min
I have noticed the car running cooler but attributed it to the cold snap we had last week. I had made a run to the store, came home and went back out to the inspection so it's possible I didn't let it get hot enough.
My CO reading last year was 0.75
Headed to my shop next week.
I love SeaFoam....
Thread Starter
Drifting
Joined: Dec 2003
Posts: 1,344
Likes: 0
From: Conyers Ga
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Theres a zillion threads on it and Im sold on it. Its $5 at Autozone. Id leave the EST connected also, depending on the smog tech they may fail it if your check engine light is lit from unpluggin it.
Id get your car nice and warm and see if someone you know can do whats called a pretest to see where you are at, you might not need anything at all.
Id get your car nice and warm and see if someone you know can do whats called a pretest to see where you are at, you might not need anything at all.
Pro
Joined: Feb 2005
Posts: 658
Likes: 1
From: Centerville OH
I had the exact same problem with my last smog check that you are having now. The problem turned out to be a sticking EGR valve. I held an inspection mirror under the valve and tapped on the body of the valve using a hammer and a long socket extension. The valve moved after 2-3 taps. I immedately jumped in the car and drove to the inspection station. VOILA -- I passed. 
Thread Starter
Drifting
Joined: Dec 2003
Posts: 1,344
Likes: 0
From: Conyers Ga
Theres a zillion threads on it and Im sold on it. Its $5 at Autozone. Id leave the EST connected also, depending on the smog tech they may fail it if your check engine light is lit from unpluggin it.
Id get your car nice and warm and see if someone you know can do whats called a pretest to see where you are at, you might not need anything at all.
Id get your car nice and warm and see if someone you know can do whats called a pretest to see where you are at, you might not need anything at all.
Thanks for the tip gentlemen..........
Thread Starter
Drifting
Joined: Dec 2003
Posts: 1,344
Likes: 0
From: Conyers Ga
I had the exact same problem with my last smog check that you are having now. The problem turned out to be a sticking EGR valve. I held an inspection mirror under the valve and tapped on the body of the valve using a hammer and a long socket extension. The valve moved after 2-3 taps. I immedately jumped in the car and drove to the inspection station. VOILA -- I passed. 
Le Mans Master
Joined: Nov 2002
Posts: 7,080
Likes: 0
From: Corvette valley Georgia
St. Jude Donor '06
HC/ppm 065 allowed: 152 passed
CO% 1.57 allowed 0.97 failed
NO/ppm: 0477 allowed: 1082 passed
CO+CO2% 15.5 allowed 6.0 min
I have noticed the car running cooler but attributed it to the cold snap we had last week. I had made a run to the store, came home and went back out to the inspection so it's possible I didn't let it get hot enough.
My CO reading last year was 0.75
Headed to my shop next week.
CO% 1.57 allowed 0.97 failed
NO/ppm: 0477 allowed: 1082 passed
CO+CO2% 15.5 allowed 6.0 min
I have noticed the car running cooler but attributed it to the cold snap we had last week. I had made a run to the store, came home and went back out to the inspection so it's possible I didn't let it get hot enough.
My CO reading last year was 0.75
Headed to my shop next week.
Make sure that the climate control is OFF so the fans are not running and let it get as hot as the fan controls will let it, the next time you get it tested. Good luck!
Drifting
Joined: Oct 2006
Posts: 1,934
Likes: 3
From: Citrus Heights California
I keep my timing at 11 degrees and run my fuel pressure at 44 lbs. Before a smog test I set the timing to 4 degrees and the fuel pressure goes to 30. I disconnect the fan and let it get hot about 240. Then I bring it in for a smog. I change the setting back as soon as possible. My 88 runs lean at these settings and passes OK.