2000 Pontiac Bonneville MISFIRE

2000 PONTIAC BONNEVILLE
171,000 MILES • 6 CYL • 2WD • AUTOMATIC
Avatar
ACSHIRLY
  • MEMBER
  • 1 POST
I have taken my car to the shop several times and they put the computer on it and say that all it shows is a random misfire, which the mechanic says could be several different things. They checked the wires,the coils,I had them to replace the plugs again
last week, just in case they had gone bad. I got the car out of the shop on Friday,August 13,2010 and drove it to work on Monday the 16th(aprox 70 miles)
and the same thing happened. It started skipping and then the service enginge light came on. I made a stop in town and when i cranked the car the light went out. The weird thing is when the light comes on the engine seems to smooth out and run better.
I love the car but this is driving me crazy because i am nervous about being on the interstate and breaking down. PLEASE HELP
Aug 17, 2010 at 8:11 AM
Advertisement
Avatar
RASMATAZ
  • CAR REPAIR CONTRIBUTOR
  • 75,992 POSTS
Misfiring can be cause by the following:

1.Defective spark plug
2.Inadequate spark/coil,defective spark plug wire.
3.Lack of compression
4.False air leakage.
5.Faulty fuel injectors.
6.Insufficient fuel pressure.
7.Contaminated fuel.
8.EGR valve that is leaking.
9.Oxygen sensors.
10.Throttle position sensor.
Aug 17, 2010 at 12:39 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.