[QUOTE=danieldc;1551142] It had a multiple cylinder misfire. Installed new plugs and wires, changed a bad ICM, replaced a weak coil pack, put fresh gas in it, and had it running right. New brakes on all four corners has it stopping right. Then I discovered it had no heat and had to replace a bad air mix valve. I've been finding alot of good info on this site to get me through fixing it up. QUOTE]
Congratulations on your work.
If you haven't check, what is the status of the UIM and the LIM gaskets? Original? Replacements? If not sure, watch coolant level carefully and consider the APN sleeved upper and the GM aluminum lowers in your future.