1989 Chevy Cavalier Help me :(

1989 CHEVROLET CAVALIER
Avatar
TLMAHAFFEY
  • MEMBER
  • 1 POST
1989 Chevy Cavalier 4 cyl Automatic 90000 miles

My car has recently began to get HORRIBLE gas mileage, there's some black smoke coming out of the exhaust pipe, it idles really rough and sometimes dies when idle. My service engine soon light is on, but no scanner will read any codes. I've replaced and/or cleaned the primary o2 sensor, the EGR valve, the idle air control, new spark plugs & wires, recent oil change, and new fuel pressure regulator. I am at a complete and total loss as to what I should do next. I was thinking maybe fuel injectors? but I don't even know how to test them.

Thanks in advance for your help!
Oct 19, 2010 at 10:10 PM
Advertisement
Avatar
RASMATAZ
  • CERTIFIED EXPERT
  • 75,992 POSTS
Hi tlmahaffey, Welcome to 2carpros and TY for the donation

Probable causes of an engine running rich are as follows:

1.Excessive fuel pressure can be cause by restricted fuel return line or defective fuel pressure regulator.
2.Defective Oxygen Sensors.
3.Leaking injectors and fuel pressure regulator.
4.Coolant temperature sensor out of calibration.
5.Restricted air intake system.
Oct 19, 2010 at 11:04 PM