I have a 03 f150 fx4, the other day after changing the intake manifold and gaskets do to it leaking coolant it started to make a loud whistle while driving 60mph plus. I have trying reving the engine but I can not duplicate the whistle. Only at 60 plus. I checked for vacuum leaks and can't find any. I am not through in any codes. Any help would be appreciated.

 

i noticed in the supercrew thread that you have a roof mounted light bar. that is what is making the whistle. i dont personally have one, but theres a lot of members on here that do and all whistle

 

this ought to help you out
https://www.f150forum.com/f6/lightba...le-fix-285792/

 

I will look into that but I have had the light bar on for a few weeks now and this noise started a couple days ago.

 

Thinking about you are probably right. I remembered that I did adjust the angle of the light bar. Doing that adjustment was right before changing the intake and messing with all the vacuum lines under the hood.

 

awesome glad i could help

 

Thanks. I completely forgot I adjusted the light bar.