After an auto-x this weekend something is howling like a banshee under the car. It only does it at full throttle high rpm 4500+. No noise at part throttle high rpm.

Anyone have any ideas?

Background:

I recently had my AEM EMS installed and am making more power now.

Car has 25k miles on it.

Have also recently (within last month) changed tranny fluid to redline MT-90

Transfer Case has been replaced at 13k miles by Mitsu (I paid for it, rather my insurance company did) and needless to say it leaks.....

How can I narrow it down to which item is making the noise? Tranny or TC?

Thanks for any help.

 

I was thinking boost leak but the whinning from them usually gets quieter in upper RPMs

 

the odd thing is, after driving in to work....it only occurs at full boost, wot.

I drove it half throttle to 7000rpm....no noise.

It makes me think boost issue/turbo noise.

But I am making full boost.

Would the turbo whine be considerably louder after removing the stock MAF and all I am hearing is the turbo spooling, just louder than before? I ran on the AEM with only 10psi for a week while I worked out part throttle issues and this whine showed up after we added full boost to the car.

 

thats was such a real sexy mama car!!!

 

yes, it is much louder without the stock MAF. Could still be a boost leak though, do a pressure test just to be sure.

 

If the car didn't change from the beginning of the autocross to the end of the autocross then I doubt is just the trubo. Its more than likely a leak.

 

I got you....I could have had the boost leak before and now the AEM is just driving the boost control solenoid duty cycle harder to achieve my target boost and I am losing pressure at a leak. Hmm.....I have t-bolt clamps on all the upper stuff but I need to remove the plastic undertray to finish it up.

 

no boost leak and I changed the remaining driveline fluids (Diaqueen)

Noise is still there. I think it has to be the turbo. It only occurs at full boost and WOT.