98 4.6 vacuum leak?
 

When I'm at a complete stop and have all accessories turned off there is a loud whining noise coming from the middle of the dash. I'm guessing that it is actually coming from the engine compartment. Has anyone experienced this on their truck? It's a 98 4x4 with the 4.6. Could I have a vaccume leak somewhere and thats what the noise is?? If I put the engine in park is seems to go away but then it comes back when in drive and not moving. When the engine is under load. Any ideas?? :help:

Possible vacuum leak going to one of the actuators in the dash.

Turn the selector to "vent". Still here it?

If so - The 98 Vacuum lines plug-in is visible and easy to get at under the dash. if you look in the right spot . Sitting in the driving position about 4" above your right ankle to right is a plug-in with 4 or 5 different colored lines. Check that for leaks.

Well I took it in to the Ford dealership and they said the noise I'm hearing is normal and that it was coming from the IAC Valve. Normal my A$$. Nothin but crooks!

Do you have an after market intake? Well , IAC 's do make noises . But you said a "whine" - The don't whine that I know of.. I take that back , they do whine when its colder than sh^t out side lol.

When they do whine in that circumstance, it almost sounds just like a bad power steering pump lol .


Read This -

https://www.f150online.com/forums/sh...d.php?t=320754

Does the whine sound like this? -

http://s131.photobucket.com/albums/p...nt=snowfun.flv

No thank god. Mine is more of a whistling sound. Can hear it at a stop light inside the cab, but as soon as I give it gas, it goes away. :o And yes I do have an aftermarket intake.

My 97 had pinhole in the lines that run from the engine to just behind the battery. I found them by keeping the engine running and spraying the lined with a squart bottle. When the sound stopped for a second and returned I looked in that area.

The dealership said it's the IAC . You do believe them right ?

Sweeet, I have this noise and I think you are right about that....It only happens when its around 0'f ive noticed.