I have a 200 xlt extended cab 4wheel drive with the 4.6. Lately when it has gotten colder when I pull up to a stop sign the thing starts to idle up and down and has died a couple of times. Also sometimes when it has done this I get a weird kind of humming sound that seems to come from the brake booster. Any suggestions thanks

 

Vaccuum leak??

 

The rough idle sounds like a vacuum leak. I don't think it's the brake booster humming though.

-Jon

 

I replaced my booster as it too started to make noise. But come to find out it was the vac. line that runs to the booster. I replaced it. No more noise. Now I have a extra booster for sale. Anyway I hope this helps!
Lariat#1