Automan1988
New Member
- Joined
- Aug 26, 2007
- Messages
- 30
- Reaction score
- 0
- Points
- 0
- Location
- Longview, WA
- Vehicle Year
- 1992
- Make / Model
- Ford
- Transmission
- Manual
I have a 92 4.0 and after it idles for a few minutes it will drop down to around 500-600 RPMs. I recall reading that if you stick a dollar bill at the tail pipe and it sucks it in you could have a burned exhaust valve. Could a miss also cause the dollar bill to do this? Also would a burned exhaust valve cause it to start idling rough after a few minutes and have no affect during normal driving. Any ideas?