Hello,

I have an 08 Mustang GT 5 speed that has a high-pitched whistling noise (not a squeal) whenever I start the car in the cold. It usually lasts a couple of minutes. Sounds like a vacuum leak; however, I cannot find where it is coming from.

The car has a C&L CAI and Magnaflow Cat-backs on it. I have checked to ensure that the CAI is fitted properly.

Any input is appreciated!

V/R

 

Does it go away after it warms up?

 

Yes, the whistling does. I'm not sure to what extent the vacuum leak disappears though... The leak may just change frequencies hence no more whistle. Thoughts?

 

Mine did the exact samething u are describing. I was never able to figure it out but always went away once the car warmed up for a few min. I had checked everything. After adding the s/c i never heard it again. Im def interested if anyone found out why it does that.

 

Thanks for the input- I appreciate it. Hmm, I like your solution. If i bolt on a s/c, then I probably would just enjoy the "whine" over the whistle ha.

Anyone that has had this similar issue, let us know how you resolved it!