Mechanics

MISFIRING WHEN THE ENGINES WARM

1994 Ford Ranger

Hi Guys. I'm having slight trouble with my '94 3.0V6 Ranger, approx 60K miles. When the engine is cold, then truck runs fine but once the engine warms up, the truck misfires constantly. I've done serveral part replacements; new plugs, leads, cap and rotor, even the coil. My mechanic thinks it could be the distributor itself. Any ideas? By the way, this only started to happen when I replaced the plugs and wires. I checked and rechecked the wires and plugs. When my mechanic checked the wires and plugs he mentioned the misfire wasn't from any specific plug, more sporadic.
Thanks again, Phil
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Pthompson
April 7, 2006.



Random misfires that jump around from one cylinder to another have an underlying cause that is often a lean fuel condition, which may be due to a vacuum leak in the intake manifold or unmetered air getting past the airflow sensor, or an EGR valve that is stuck open.
Did you try putting back the old plugs and wires?

Good hunting and let us know. : )

Tiny
Peppermrj
Apr 8, 2006.
Thanks for the info. I replaced the EGR valve, I'll have a play with the truck this weekend.

Tiny
Pthompson
Apr 19, 2006.
Well, here's the answer to the fix. However, before I tell you, there's a leason to be learned. Never listen to your friends that say they're " car savvy". Always go with your gut instinct. My gut instinct kept telling me that the new spark plugs I had just put in were faulty. My mate kept telling me there's no chance that would happen. Well, the ceramic was cracked on one of the spark plugs which made the car buck like a bull when it was warm. ALWAYS CHECK YOUR PLUGS. EVEN IF THEY'RE NEW! Thanks for all the help.

Tiny
Pthompson
May 17, 2006.
Thanxs for the update. Good advice. I have heard of that more than once. Not very common but a real PITA. : D

Tiny
Peppermrj
May 17, 2006.