what's that sound?

[calh4289]

Sorry if this has been addressed before. I have done a lot of searching and am at a loss at this point.

Car is stock 2003 6Speed with aftermarket DV's and BMC air filter. 23k Miles.

I am consistently hearing a howling noise that can be best described as air rushing through a pipe (kind of like when you blow air across a bottle opening). I think it is coming from the rear passenger side. This happens in 3rd-6th gear when the RPMs are in the 2700-2800 range and I am cruising with little throttle (no boost registering on the instrument panel).

I brought the car to the shop and the car was diagnosed with a faulty diverter valve, so I had them changed with aftermarket DV's. I also had the power steering reservoir changed as it was squealing. Still the sound continues. It is quite annoying because the howling sound is constant while under cruising RPMs.

Any other ideas of what I should look into? Thanks!

Also, sorry for the newbie TT question, but is it normal to hear a similar winding down/ air rushing out a pipe sound when exiting the hwy onto off-ramps even when the car is not showing boost?

[Loren]

Perhaps this?

Have a look at TSB 1/05 4897 Loud Whistling Noise From the Engine Area

"Loud whistling noise from the engine area.

A loud whistling noise can be heard from the engine area while driving the above-mentioned vehicles. The noise can be heard clearly both inside and outside the vehicle. The noise goes away for a short period when pressing the clutch pedal. This noise is caused by the pressure control valve in the steering oil reservoir. This valve vibrates strongly when hydraulic oil flows through it at oil temperatures of more than 212° F. (100° C). To remedy this concern, steering oil reservoirs with a modified pressure control valve have been installed in vehicles manufactured since February 23, 2005."

[calh4289]

Thanks Loren. I actually had the Power Steering reservior changed, but that was a high pitched whining sound. That problem was resolved. The sound that i am hearing is more of a howling sound only at cruising rpms.

Edited September 23, 2012 by calh4289

[Sunnyside]

Does it still make a noise when you turn off the aircon ??

[calh4289]

Yes, the sound can be heard with or without the a/c turned on.

[wross996TT]

Have you had your system tested for vacuum leaks?

[calh4289]

No. I guess that will be next on the list. I've seen a lot of boost leak test kit threads. Any advice for testing myself?

Edited September 23, 2012 by calh4289

[Richard Hamilton]

Does it boost to 0.6-0.7 bar at WOT?

[calh4289]

Yes. I hit .6 regularly. Not in every gear, but I do get full boost.

[Sunnyside]

Yes. I hit .6 regularly. Not in every gear, but I do get full boost.

Anychance you can get some one to record the sound and attach it so we can all hear?