Originally Posted by cruiser54
Timing being off does not cause rough running. It's a term that gets thrown out there, mostly by those ignorant of how engines work.
Vacuum leaks been checked? Intake manifold bolts loose? Throttle body and IAC been cleaned? CCV hoses and piping clear and clean?
think crusier54 may be on to something with the manifold bolts. I had a new 85 cherokee that exibited a rough idle. It would change idle when hot vs cold. It was eventually traced to a bad intake manifold seal ( i dont know if it really had a gasket in it. per the dealer.) I changed everything to fix it and finally left it at the dealer. After 3 days, i got a call to pick it up. It was the smoothest running engine I had ever seen. ( had to always give it gass to get it to run.) The dealer had removed and reinstalled the intake manifold.