1995 Pontiac Firebird missfire and rich fuel mixture

102,000 MILES • V8 • 2WD • MANUAL
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LIMO1644
  • MEMBER
  • 1 POST
My transam is running rich and feels like it's not running on all 8 cylinders.
May 22, 2010 at 4:08 AM
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RASMATAZ
  • ✓Experienced Mechanic
  • 75,988 POSTS
Hi limo1644, Welcome to 2carpros and TY for the donation

Probable causes of an engine running rich are as follows:

1.Fuel pressure not within specs.Can be cause by restricted fuel return line or defective fuel pressure regulator.
2.Defective Oxygen Sensors.
3.Leaking injectors.
4.Coolant temperature sensor out of calibration.
5.Restricted air intake system.
May 22, 2010 at 4:42 AM
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