[updated:LAST EDITED ON 15-Jan-02 AT 08:04 PM (EST)]I took my truck to an exhaust shop a few weeks ago after suspecting an exhuast leak, but they told me the leak wasn't underneath, that it was a vacuum line up on top, and that they send the trucks to a Ford dealer to be fixed. I know I don't want to send it to a Ford dealer if I can do it myself. How expensive is the part, what am I getting into by attempting to replace it, and what's the best way to pinpoint exactly where the leak is? Also, the leak isn't noticeable at idle, only at higher rpm's under load (going up a hill). This leak makes my Inline Six sound like a toy going up a hill Thanks for any help

 

To find your leak, spray carb cleaner on all the vacuum hoses and connections, you'll know when you find a leak by the change in rpm. Just be careful around hot exhaust pieces, a cold engine would be safer to do this on.

The hard plastic lines used are prone to cracking and breakage after time. Most people replace these with soft rubber line.

 

I think what they were referring to is the Air Injection Manifold , If one of its tubes are broken you wont hear the exhaust noise at idle , only when the truck is moving will you hear it .

 

That's it. Forgot the name of it. Do you know how expensive it is, and should I take it to a shop or can I do it?

 

Im guessing its about $70 or so from Ford . You will have to remove the upper intake manifold to gain access to the pipe . The labor charge to remove & reinstall the pipe is about 3 hrs so thats likely close to $200 for labor alone . Reinstalling the Air pipe is the hardest part . Start in the middle & alternately work back & forth tightening the nuts of the pipes . Spray the nuts down with some PB Blaster or some rust penetrant to loosen them because they will likely be rusty . Its not a hard job of you have the tools , Mark all the vacuum lines bcause the ones that run across the intake will have to be removed , Egr pipe or the valve itself will have to be disconnected . The air diverter valve & some of those hoses will have to come off & you will have to remove the check valve that screws into the air pipe , youll have to rreinstall it on the new pipe .