1998 Volvo S70

Engine Performance problem
1998 Volvo S70 6 cyl Front Wheel Drive Automatic 147000 miles

My check engine light goes on and off and just recently I decided to take it to autozone to get the engine fault codes. They told me to call the Volvo store since they didnt have any explanations for volvo codes. The volvo store ended up telling me their numbers were different and i'd have to spend $100 to come in for a diagnostic by them and leave it over night. To try to avoid all of that I was wondering if anyone had any clue what these error codes could mean on a 1998 volvo S70:


Whenever the check engine light comes on, my rpm's start faltering and when I come to a stop, my engine stalls and i'll be stuck in the middle of the road. The electrical system still works, my radio and air conditioning remain on.
February 25, 2010.

Volvo trouble codesare different and more precise. PO171 is for a fuel trim problem but would need to know if t is running too rich or running too lean. The other code I do not know what that is? For your fuel trim problem you would need to check for proper fuel pressure, you would need to smoke the intake side to check for leaks and you would need to pressure test the exhaust system for leaks. Any unmetered air from the intake or exhaust leak the oxygen sensor picks up and causes the light to come on. You should also check for fuel contamination in the oil. If all that looks good then the mass air flow sensor could be faulty.

Mar 1, 2010.