michaela8456

I have a 1989 mustang gt convertible has the stock ho 302 motor pulled spark plugs and put new ones in the old ones looked great but still idels fast and ruff any ideas what it could be please help thank you when driving runs great just ruff idel at stop lights or just sitting

dawson1112

If it idles ruff you should take the dog out of it
J/K lol

Sounds like you could have a vacuum leak some place.

michaela8456

no vacuum leaks

88 orangepeel notch

Are you talking about an rough lopey idle like it has a big cam, or surging idle where it idles at 700rpm then 1300rpm, then back down to 700?

michaela8456

yes , surging 700 to 1300 up and down does it off and on not always study do you think i need to clean maf sensor or what thanks for your reply please help with any thoughts

88 orangepeel notch

Yeah, that would be a good start to try a narrow it down. If you do a search for "surge", you'll be reading for days on all the threads on it. And how they fixed it.