failed emission test, what to do first?

Messages
49
Location
Lansing, MI
91 pontiac grand am, 2.3L quad4. Car runs fine. Might be a very little bit of roughness at idle. Drove ~ 10 miles before test. Outside Temp 63 F. coolant Temp at 160-220 F after driving for 2 miles maybe. Here is the result. idle 2500 limits HC PPM 375 161 220 co% 0.01 1.55 1.2 co2% 12.6 12.2 RPM 920 2517 Running rich? What to do first? Thank you very much!
 
Messages
2,620
Location
in the shop
I know several guys who have used Tolene (sp) and/or acetone in their tanks (premixed with fuel). They tell me it will make vehicles pass emissions up here in Colorado for some unknown reason. I think it sounds crazy but it may be worth looking into (google perhaps). I have seen them mix a few healthy ounces in with a gallon of fuel. Good luck. I would try using a tank full of the emission pass stuff they sell at checkers. Then run the car for a good while to get everything nice and hot before the test.
 
Messages
4,286
Location
Central Wisconsin
strong dose of injector cleaner(gumout Regaine) new PCV valve. new air cleaner. spark plugs. check for exhaust restrictions, 'Italian Tune-up' just before re-test.
 
Messages
4,286
Location
Central Wisconsin
There are additives that can be added to the gas before the test. They claim to improve chances of passing. Auto parts store; don't recall seeing any of these at Wally World.
 
Messages
936
Location
Pittsburgh,PA
quote:
Originally posted by dwendt44: strong dose of injector cleaner(gumout Regaine) new PCV valve. new air cleaner. spark plugs. check for exhaust restrictions, 'Italian Tune-up' just before re-test.
I agree 100% Also, I wouldnt use any solvents in your tank or any other additives DURING your emissions test. Toluene, acetone, and some others are known to kick up HC emissions, that would be counterproductive here. They might help clean the system but dont let them be there for the test. I just faced my emissions and passed with flying colors. Up to then for the last 2 months the car has been on a steady MMO+Lucas diet. With a couple regane treatments thrown in. My readings were HC: 37ppm idle 30ppm 2500RPM CO: .09% at both idle and 2500rpm Here in PA they dont measure CO2.
 
Messages
3,329
Location
Bolivia
When my daughter's Subaru faild the Virginia tests, I ran a tank with Techron. The next week it passed with flying colors.
 
Messages
882
Location
North Carolina
I echo the injector/combustion chamber cleaner comments. Maybe a tank of E10 gasahol if available before and during the test? [I dont know] Try the cheap fixes 1st of course. FWIW my long gone '85 Camaro with a failed Cat (gutted on its own) but otherwise in sound condition (>200K miles) barely passed emissions back in the early '90's using this technique (gasahol). Good luck.
 

chromatin

Thread starter
Messages
49
Location
Lansing, MI
Hah, thank you guys! OK, here is the thing. That engine has no PCV. Weird, hah! It uses an oil/air separator system. No code, no check engine light. Already poured a bottle of g2p into it last night. Will go to replace the air filter in a minute. Now a small problem here though. The g2p bottle says I have to use up the current tank and then fill up with another tank before doing the retest. There's no way I can use up the current tank with my regular driving profile in 3 weeks. The FREE re-test is only valid in 10 calendar days. I happen to have a ~120 miles round-trip next weekend. So here is what I am doing. When I come back, do the test. Pass? great! Fail? wait until the current tank is empty, fill another tank, Italian tune-up and go for test. Still fail? Think about doing something else. Any other thoughts? I think this is the best way, time and money wise. BTW, in another forum, a guy with a High output version of this engine failed even after spending 1000 bucks on o2 sensor, cat, egr, plugs, wires, coils, maf sensor... Then he poured a bottle of g2p and it passed!
 
Messages
475
Location
SoCal
What about NOX? Does your state test for NOX? The reason I ask is I just (barely) passed my California emissions test yesterday. CO and Hydrocarbons were so low as to be almost non-existent, but my NOX was within 5 ppm of failing! 1995 Saab 900S with almost 206,000 miles on the odometer. When I was in Colorado (where the car was purchased new in 1995), the engine was so clean I didn't have to get it smog tested except every couple of years. Moved to Cali in 2003, and INSTANTLY car had trouble passing NOX, always has. Steady diet of FP60 MMO Lucas combo. Used premium fuel for the test. Go figure.
 

chromatin

Thread starter
Messages
49
Location
Lansing, MI
Here in Northern Colorado doesn't test NOX. Actually this year (only three months left) is the last year they ask for emission test. The law is expiring and they are not going to renew it.
 
Messages
4,286
Location
Central Wisconsin
"Steady diet of FP60 MMO Lucas combo. Used premium fuel for the test" Those might have contributed to your NOX reading. If an engine will run on regular, use that for the test. Try the 'italian tune-up' next time.
 
Messages
7,077
Location
Ontario, Canada
If one injector is plugged a bit, that cylinder will run lean. The computer will see the extra oxygen in the exhaust from that one cylinder, and richen them all until no more oxygen is detected. Then you end up with that cylinder runing just right, and the other three running too rich. Maybe the cleanser will work for you.
 
Messages
591
Location
Pittsburgh PA
I had a 95 grand am with the 2.3l Quad-4 when it failed I put a new oil/air seperator in with all new hoses to it. Also replaced the O2 Sensor and plugs and she passed with flying colors. One thing I noticed is that engine is hard on plugs, they were pretty worn. After doing some checking I found out it specs "double platinum" plugs. BTW I had recently changed the oil,oil filter,air filter before the first test FWIW.
 
Messages
936
Location
Pittsburgh,PA
Wouldnt running too high an octane fuel cause an increase in HC rather than NOX. Nox is due to running lean ie too hot during combustion. Running a gas that cant fully combust would produce a high HC reading. Usually I hear you should run the lowest octane your car can take during an emissions test since its the easiest for it to fully combust. Heck, at todays gas prices I think thats a good general rule to run the lowest octane(cheapest) gas it can effectivly operate on.
 
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