Tune up thoughts

i just went to get my 92 inspected for emissions and it failed and i have noticed that it seems to be running a little rich lately. Im not excatly a master mechanic, and i was wondering what anybody would recomend to slove my little delima. (ie tune up tips and what not) thanks for any wisdom
Josh

Did they have oxygen sensor's back then? Usually when the sensor goes, it allows a richer mixture. Also dirty air filter on an older engine will cause it to run richer. I'm assuming you running fuel injection, so there isn't a carb issue...

Dacula92xj said:

i just went to get my 92 inspected for emissions and it failed and i have noticed that it seems to be running a little rich lately. Im not excatly a master mechanic, and i was wondering what anybody would recomend to slove my little delima. (ie tune up tips and what not) thanks for any wisdom
Josh

Click to expand...

What pollutants does your state test for, and what are the readings (both allowed, and what your vehicle tested)?

Should be entries for CO, HC, and NOx

Eagle said:

What pollutants does your state test for, and what are the readings (both allowed, and what your vehicle tested)?

Should be entries for CO, HC, and NOx

Click to expand...

I live in GA and there are two parts to the test, the 25/25 test and a 50/15 test. On the 25/25- HC ppm 159 allowed, reading was 130. CO% 1.78 allowed reading was 1.50. NOx ppm 1014 allowed reading was 1596 failed. then in the 50/15 test- HC ppm 163 allowed reading was 113. CO% 1.38 allowed reading was 1.75 failed. and on the NOx ppm 1110 allowed and the reading was 1193 failure. I hope that means something to you eagle. I appreciate any help.
Josh

Just for the sake of overall engine health and to help pass the emissions test, I recommend the following:

• Replace the spark plugs or at least remove, clean and regap them
• Replace air filter
• Change oil & filter (has an effect on emissions test
• Replace cap & rotor
• Replace O2 sensor if it's old or the last time it was replaced is unknown
• Clean throttle body

How old is your catalytic converter?

Tom

High NOx emissions in the face of normal or low CO and HC emissions indicate that your engine's running too lean. You don't have an EGR valve that could get stuck open so it's likely that you have a fuel delivery problem e.g. clogged injectors, clogged fuel filter.

The cat has been replaced recently but has takin a couple of pretty good hits, so is it it possible that i knocked some of the crap out of it. the reason that i thought it might be running rich is that when i crank it sometimes it taks awhile and i can smell gas and it will backfire sometimes which i have been told is a symptom of it running rich.