Hello everyone, I have recently developed a vacuum leak on my 2002 F-350 V-10 under the passenger side of the dash. It is only audible when I am accelerating moderately to heavily or when the truck downshifts going up a hill. None of the vehicles HVAC or ESOF functions seem to be affected by this leak from what I can tell, but it's rather annoying to listen to this loud sucking noise every time I hit the gas moderately hard such as climbing a hill or merging onto the freeway. I don't know how I could search for this leak since it only happens when I'm driving and accelerating and not at a stop.

Anybody have any idea what might be going on or where I should begin my search?

Thanks!

 

put the rear wheels up on jack stands/chock the fronts and accelerate away. in 2wd.

 

If you don't have one, get a vacuum guage and hook a long tube under the dash and tee into one of the lines coming from the engine compartment to see if there is a large vacuum change during this issue.

If so, you have a place to start.

If not, you need to get someone to get their head down there while you are driving to try and diagnose the issue.

Good luck, Tom