SPONSORED LINKS

1996 Pontiac Sunfire Runs rich

Tiny
OTISV793
  • MEMBER
  • 1996 PONTIAC SUNFIRE
  • 4 CYL
  • FWD
  • AUTOMATIC
  • 123,350 MILES
My sunfire runs rich all the time. Replaced the oxygen sensor MAP and fuel pressure regulator. Check engine light on for lean condition. The oxygen sensor voltage never gets above.3 volts. On occassion it will clear up and run fine for a few days and the light will go out only to come back again. This has benn an on going problem but has become much more frequent lately.
SPONSORED LINKS
Tuesday, March 3rd, 2009 AT 4:18 PM

1 Reply

Tiny
JAMES W.
  • MECHANIC
  • 2,394 POSTS
You probably already know this, but the O2 sensor range is from.1 volts (rich) to.9 volts (lean). My first thought is: the O2 sensor is sending a rich signal (.3 volts) to the ECM but the ECM is not processing the signal correctly and still thinks the 14.1 to 1 fuel ratio it's trying to maintain is still too lean so it is adding more fuel. I'm not one to blame the computer first for all of an engine's ailments, but this time it may be the cause. You may want to have this checked out.
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Tuesday, March 3rd, 2009 AT 9:53 PM

Please login or register to post a reply.

Related Engine Rich Content

Is it Safe to Drive Check Engine Light?
VIDEO
Is it Safe to Drive Check Engine Light?
Instructional repair video
Engine Running Rich
GUIDE
Engine Running Rich
This guide was created to show you what can cause an automotive engine to have a rich fuel mixture, which may cause black smoke to be released form the exhaust tail pipe as...
VIEW MORE

Sponsored links