For the last year or so, my 2000 F-150 has made a strange rattling/clicking sound that appears to be located just above the transmission tunnel near the HVAC vents. It seems to go away in the winter months and come once it warms up. It doesn't gain speed with the HVAC fan speed but does almost sound like a fan or impeller is hitting something. I popped the cover off on one side but couldn't see anything.

Does anyone have any idea what this might be? I am tired of hearing it and need to do something about it. Thanks.

Greg

 

I don't know if it's the same problem, but my 99 Expi does a similar thing when the AC is on and the fan is on low. It almost sounds like a Jake Brake on a truck in the distance. Kinda wierd. Once the fan is turned u-p the sound goes away.

 

Thanks for the reply. Anyone else?

Greg

 

I had a 99 Windstar that had a rattle at the center of the dash and it was the airbag control module. There is a little ball that rolls around inside the module and can rattle a little. They replaced two of them and they both made the same noise. Also on my 01 F-150 I had a snapping/popping noise that I could quell if I loosened the cover that surrounds the radio and HVAC controls so it stuck out a bit off the dash. Try that. R81