2008 Mustang GT with noise from dash

ragtopnc · 12-29-2008

Hi all,
have an '08 Mustang GT ragtop. Love it. have a problem with a noise. here's the general synopsis;
usually only heard after start up,
engine/trans cold (auto trans),
it's kind of a whining/vibration noise resonating out of the dashboard air vents (basically out of the dash area) during acceleration momentarily after shifts and while accelerating.
Is that confusing enough? The dealer hasn't looked at it yet, mgr said it is probably a belt loose, showing up when it is cold and damp? I believe a serpentine belt has auto tensioner thus is it truly a loose belt?
Car only has 8000 miles on it.
Any suggestions. By the way, I had a tall cup of soda sitting in the cup holder and could feel a vibration when the noise occurred.
Thanx, ragtopnc

**stlwagon** · 12-29-2008

Welcome... I'd suspect it's the center stack rattle. There is a TSB out on it. Check the TSB sticky thread up above. If it's not that, then it's likely the plate between the transmission bellhousing and engine that's rattling.

travelers · 12-29-2008

Yep, that's what it sounds like to me.

six5mustangfan · 12-30-2008

I have the exact same problem with my car. How should I fix this?

BruceH · 12-30-2008

I started out without it. Went to a FRPP CAI and tune and had it a little. Went to a custom tune and it really buzzed especially around 4K. Just went to a Whipple with the FRPP/Whipple tune and it's almost gone.
I think my flexplate has a resonante frequency and that some tunes get it to rattle more than others.

**stlwagon** · 12-30-2008

Quote:

Originally Posted by BruceH

I started out without it. Went to a FRPP CAI and tune and had it a little. Went to a custom tune and it really buzzed especially around 4K. Just went to a Whipple with the FRPP/Whipple tune and it's almost gone.
I think my flexplate has a resonante frequency and that some tunes get it to rattle more than others.

I have the plate rattle real bad. It's going to have to wait til Spring..

travelers · 12-30-2008

Quote:

Originally Posted by six5mustangfan

I have the exact same problem with my car. How should I fix this?

Set fire to it.

J/K

ikanncu76 · 12-30-2008

I have the same problem coming from the farthest left vent. Its a small rattle that comes once I get on the freeway. You should get it checked you did pay for the warranty.

Thereaper · 12-31-2008

Quote:

Originally Posted by stlwagon

I have the plate rattle real bad. It's going to have to wait til Spring..

What's required to fix the plat problem ?

**stlwagon** · 12-31-2008

Quote:

Originally Posted by Thereaper

What's required to fix the plat problem ?

The expensive fix involves dropping the transmisison and replacing that plate. The cheap fix is to add some rubber washers between the bellhousing and the plate..