2006 Mustang 12k automatic

I am hearing a whistling sound when accelerating. It only seems to happen in second gear. I checked the intake and all is tight. Throttle body is tight as well. If I give it a lot of gas, from a stop, 1st gear is ok, 2nd gear loud whistle until 3rd gear shift. also there is a slight delay in shifting from 2nd to third, it kinda hangs then lunges into 3rd.

Sounds like a vacuum leak of some kind. It could just as easily be under the dash if one of the mode door vacuum lines is leaking.

Fords have a lot of problems with the rubber connectors for the larger vacvuum lines like the PCV where it attaches to the manifold. They suck a hole right through the rubber.




78 Corvette Pace Car For Sale-18k mi orig-Florida

Took it to the dealer and they concluded that it is planetary gear whine in the trans. They said it was normal for Fords. If you guys agree then all is OK.

I guess that would depend on just how loud the noise is. You can write off a little bit of noise as normal but if it's real excessive, then something is wrong.




78 Corvette Pace Car For Sale-18k mi orig-Florida

Its not too loud although it can from time to time seem louder and a bit annoying. Kinda sounds like a turbo. It started to whistle about 11k miles so if I keep the car I have to listen to it for 100k more miles!

If your unsure if they are correct, take it to a trans specialist and get a second opinion.




78 Corvette Pace Car For Sale-18k mi orig-Florida

Good idea, I will ask around for some recomendations for a good mechanic. I just realized that this whistle is louder when its colder outside, could this confirm the dealers diagnosis?

The dealer could be correct about their diagnosis but wrong about it being normal. I can't confirm anything. Just get a second opinion. That's the only way to find out.




78 Corvette Pace Car For Sale-18k mi orig-Florida