I just installed some LG LT headers on my C5 and I am getting a random misfire code on cyl 3 only witch goes away after warm up. Im sure its a spark issew with a bad or loose wire. My question is how does the PCM determine what cyl is actually misfireing? Also how accurate is it? Thanks.

 

Ok can anyone answer me this? Does the computer shut down the injector on a cylinder that has set a misfire code? I ask cause the car completely smooths out when the CEL goes solid.

 

I'd be interested in finding this out also. My missfire is not very consistent. I think it's a cracked insulator. Already found one cracked. Dam AC Delcos.

 

By the crank position, to the fire order, I guess but the cpu is dam accurate!