hanging idle
Thread Starter
|
New User
Joined: Nov 2003
Posts: 3
Likes: 0
hanging idle
i have a hanging idle problem on a 94 F150 w/351W. I just rebuilt the engine a few weeks ago. I checked the IAC valve, and it checks out o.k.. I also removed it and cleaned it to make sure it wasnt hanging open.
The idle doesnt surge at all, and I cant find any vaccum leaks at all. The engine runs perfect aside from the idle hanging. If you pull in a driveway off the street and let off the gas, the idle hangs at around 1700 rpms for about 20 seconds or so, then slowly drops down to normal.
The owner said that it did it before the rebuild, and the engine had 280,000 on it. What else would cause a hanging idle?
the truck just passed emissions with no problem if that helps. The emissions guy actually said that he was amazed how well it passed.
The fuel injectors are original, and the throttle body hasnt been touched. Thanks for any help, Mike
The idle doesnt surge at all, and I cant find any vaccum leaks at all. The engine runs perfect aside from the idle hanging. If you pull in a driveway off the street and let off the gas, the idle hangs at around 1700 rpms for about 20 seconds or so, then slowly drops down to normal.
The owner said that it did it before the rebuild, and the engine had 280,000 on it. What else would cause a hanging idle?
the truck just passed emissions with no problem if that helps. The emissions guy actually said that he was amazed how well it passed.
The fuel injectors are original, and the throttle body hasnt been touched. Thanks for any help, Mike
Cargo Master
Joined: Dec 2003
Posts: 2,734
Likes: 38
From: Sunny Florida
I just replaced my throttle body. I could get it to stick at around 1200 to 1400. Check to see if you can make it stick by hand while under the hood. This should tell you if the TB is sticking.
