My wife took our 1994 Cruiser for emissions and it failed today. NOX was 6.02, limit is 4.0. Two years ago it just squeaked by with 3.9 NOX after I rebuilt the EGR system, replaced VSV and a bunch of vacuum lines.
I just replaced the air flow sensor with a rebuilt unit from Cardone after it was throwing codes 2 and 8. The codes would return almost immediately after a computer reset. I reset the computer after the new VAF was installed and the codes haven't come back. It has had five drive cycles since the computer was reset.
I don't have any codes indicating bad O2 sensors, but I'm not sure how to check them.
CO is higher than it was at the last emissions check.
So, do I still need to do more drive cycles before the computer re-learns? Do I need new catalytic converters? O2 Sensors? Just get it good and warm and put some Heet in the tank and re-test?
I'm not opposed to new parts, but I don't want to just throw cash at it. What to do?
I just replaced the air flow sensor with a rebuilt unit from Cardone after it was throwing codes 2 and 8. The codes would return almost immediately after a computer reset. I reset the computer after the new VAF was installed and the codes haven't come back. It has had five drive cycles since the computer was reset.
I don't have any codes indicating bad O2 sensors, but I'm not sure how to check them.
CO is higher than it was at the last emissions check.
So, do I still need to do more drive cycles before the computer re-learns? Do I need new catalytic converters? O2 Sensors? Just get it good and warm and put some Heet in the tank and re-test?
I'm not opposed to new parts, but I don't want to just throw cash at it. What to do?
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