Author Topic: engine revs up and down on it's own.  (Read 3734 times)


  • Newbie
  • *
  • Posts: 7
  • Gender: Male
  • Mustang: 68 coupe
  • Daily driver: 1968
  • Location: Kansas
engine revs up and down on it's own.
« on: January 01, 2011, 04:34:29 PM »
I just had the carborator rebuilt and it was set to factory specs. The problem is that after the car warms up it almost always dies when I come to a stop sign. In idle it revs up and down on it's own. This is a 68 with a 302 and 4 barrel carborator.

Anyone have any ideas


  • Photo contest winner
  • *
  • Posts: 845
  • Mustang: 1965 GTFB, 1966 GTFB K, 1966 Hardtop
  • Daily driver: 1969 VW Baja
  • Location: Northern California
Re: engine revs up and down on it's own.
« Reply #1 on: January 01, 2011, 04:50:14 PM »
You may have a vacuum leak. Check the distributor vacuum diaphram, especially if you have one of the advance-retard features on it.  Use a piece of rubber hose on the ports and with the distributor cap off, see if you get movement some "mouth" vacuum. You may also have overcompensated for your problem by increasing the idle.


  • Newbie
  • *
  • Posts: 4
  • Gender: Male
  • Mustang: 1985 GT 5spd hatchback
  • Daily driver: 2002 Ford Explorer, 1984 Ford Bronco, 2003 Chevy Impala
  • Location: The Sandhills of South Carolina
Re: engine revs up and down on it's own.
« Reply #2 on: February 09, 2011, 12:43:12 AM »
Air leak, could be as simple as the carb to intake  gasket.  My car did that after I put a new carb on, no amount of adjusments fixed, I took the carb off, and put a new gasket on, bolted it up, tuned it, now it runs good, idles right.



Other languages
In memory of our moderator Glen Wren AKA Soaring

Dallas Mustang

LO-FI Version
Mustang classifieds
Muscle car classifieds
Classic Mustang FAQ

Mustangs for sale

Top Posters

Posts: 4279
Posts: 1379
Posts: 845
Posts: 681
Posts: 471

Used Cars for sale - Ford Mustang classifieds - Forum Camaro FR

Powered by EzPortal