I have an automatic 96 chevy Tahoe,5.7L with 297,000 miles. I did the plugs, wires, cap, and rotor when I bought the truck at around 295k miles. A few days ago my motor got a misfire on cylinder 3 and began running rough.
I found a cracked spark plug in cylinder 3 and corrosion on the contact points of the cap, I replaced the plugs, cap, and rotor again and the misfire got worse and became a random/multiple misfire until i replaced the ignition coil, now the misfire is back only on cylinder 3 and cylinder 3 has spark, how do i get this misfire to go away?
misfire is also not persistent, once cleared, it takes quite a while for misfire code to pop
Have you verified the cylinder has compression?
Check your ignition control module inside the distributor. The insulating gel that keeps them cool dries out and they over heat and malfunction. About $33 at Autozone for a new one.
My Tahoe has the ICM that is separate from the distributor, it is on a bracket with the ignition coil, but while replacing my ignition coil, I removed the ICM so I could place the bracket in a vice and drill out the rivets and there was a thick, white coating on the ICM and the bracket where it connects, I wiped off the bracket but left the module alone, is this coating some sort of tell?
Yes - it is similar to the gel used in the old ignition control module and is necessary for proper function. The part number is DR178, AutoZone, $93, limited lifetime warranty.
i have now replaced the icm and i still have a misfire. im really lost here🤔