Cadillac Seville / Cadillac Eldorado Forum Discussion, 99 sts running rough after warms up in Past Cadillac Vehicle Discussion; My neighbor just bought a 99 sts after it gets to normal operating temp starts running rough and the rpms ...
My neighbor just bought a 99 sts after it gets to normal operating temp starts running rough and the rpms start surging, i did a search and it looks like it could be the icm but he swapped that already to no avail. any other suggestions? Thanks in advance, Bill
Pull the codes... post with defiitions & current or history.
There is a sticky on how to do it.
Throwing parts at a Caddy is the first wrong thing to do.
Thanks I did pull the codes, and accidentally cleared them, I only pulled the PCM codes though, I will pull the rest and get back to to u, I do know It had a random cylinder misfire, and I do know he said he had new plugs put in it, the codes I pulled were P0155 and P0440 both current, there were a few history codes but as I mistakenly cleared them I don't know what they were