1992 Chevy Lumina Timing?

JAMESNCRYS

MEMBER
1992 CHEVROLET LUMINA
6 CYL
FWD
AUTOMATIC
135,000 MILES

I have a 1992 Chevy Lumnia 3.1 v6. We've changed the spark plugs and the spark plug wires. They were both in bad condition. We have put a new fuel filter on it. Also, our pulley and the belt that is on the alternator, the belt was rubbing some where and we fixed it and replaced the pulley it self and the belt. We have had to go back and re-tighten the pulley because it loosens sometimes, but we think we've got that problem solved. The car started shifting rough and it's missing. We were told that it could be the cool pack, but we were also told that it could be jumped timing. The car shakes as it goes up hills and when you first take off, hard shifting, back fires, it also makes a vibrating sound when at a complete stop and in drive. We have to put in in neutral at a stop light to keep the car from dying. Can someone please tell me what is wrong with our car?

1 Reply

KHLOW2008

MECHANIC
41,814 POSTS

Symptoms indicates misfiring and it could be the coil packs. Diagnostic equipments should be able to determine which cylinder is is misfiring.

When misfiring occurs, the idling would be low and that would result in hesitation during take-off and stalling when idling.

Unplug the wire from each cyliner individually with engine idling. Any cylinder that does not have much changes in engine rpm would be likely to be not firing.