missfire question

[jay dcpt]

Car is a 2002 pontiac bonneville with a supercharged 3.8. Customer brought it in this afternoon with a missfire on cylinder #6. I can see by looking on scan tool that at one time it was missing on all cylinders By looking at missfire history. But the vehicle was worked on recently by another shop and the customer wasnt happy. I only looked at it for a few min today but it apears to have newer ignition wires and one new coil pack that isnt for #6. Anyway It is only missing on # 6 for me pretty much all of the time. I swaped coils and i listened to the injector with a stethascope and it sounds like its working. I figured i will get more involved with it in the morning. I was just wondering if you guys no of any common problems to look at? From what i noticed from only looking at the vehicle for a few minutes it will do it at idle when cold and when its warm it will pretty much do it at any time under any kind of load. Vehicle is stock with 190,000miles. Any suggestions?

 

[murphinator]

assuming stock pulley on sc ??

even if it has a smaller pulley #6 isnt a common cyl to have misfires in due to too small a pulley/piston chipping so I would just look at the ignition components , plug ,wire ,coil pack , or even corroded terminal on the post for #6

if all those are ok they maybe ignition control module ( located under the coil packs)

but seeing a new coil pack I would start right there

fyi sc cars get more powerful factory coils than NA or aftermarket like msd accel etc...allthough I dont think thats a factor until you are under substantial boost

 

[jay dcpt]

thanks murph ill post back what i find

 

[jay dcpt]

Dont trust the numbers on the coil packs. That was the problem

 

[murphinator]

Dont trust the numbers on the coil packs. That was the problem

ahhh somebody played the shell game lol