Opinion Needed: Motor
#4
So you've got a code for O2s, replaced them, and now the light is back on for it? I dunno, regardless how cheap you get parts, it seems a bit crazy to me to just start buying a bunch of random parts without actually investigating what is wrong with the car.
Does the place you get cheap parts carry a full function scan tool (not just a code reader)? If you intend to continue DIY repairs, it would be worthwhile to pick one up.
Does the place you get cheap parts carry a full function scan tool (not just a code reader)? If you intend to continue DIY repairs, it would be worthwhile to pick one up.
Last edited by bumpin96monte; 02-22-2019 at 11:10 AM.
#6
Join Date: Apr 2010
Location: Mentor, Ohio
Posts: 12,156
Bumpin' has a point, shotgunning parts can just waste time and money. Also, have to be careful. O2 sensors can be finicky sometimes with these cars if you don't use AC Delco (some of the other brands are not as tight to the factory spec and can cause weird issues).
If you no longer have a check engine light, but you have a rough idle:
- Check for vacuum leaks. Easy way is misting starting fluid around the engine (specifically anywhere that has a vacuum line) and listen if the performance of the idle changes (if so, you have a vac leak).
- Check for spark plug wire damage, possible arcing.
- If the plugs are over 100K miles, could be a good chance for general maintenance and refresh the plugs and wires.
I have also dealt with coils and ICM issues causing rough idles and full out mis-fires.
If you no longer have a check engine light, but you have a rough idle:
- Check for vacuum leaks. Easy way is misting starting fluid around the engine (specifically anywhere that has a vacuum line) and listen if the performance of the idle changes (if so, you have a vac leak).
- Check for spark plug wire damage, possible arcing.
- If the plugs are over 100K miles, could be a good chance for general maintenance and refresh the plugs and wires.
I have also dealt with coils and ICM issues causing rough idles and full out mis-fires.
#7
Trouble codes are only intended to guide you towards a diagnostic path of further mechanical and/or electrical testing to identify the true cause of the problem. They're not intended to be the only test to be done before replacing components.
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