ShaggyDooWRX

iTrader: (3)

Hi,

Has anyone else ever had this problem, and know how to fix it, or what the problem might be?

I have a completely standard MY03 WRX except for a bailey DV12 fitted.

For some strange reason instead of dumping off with a good strong whoosh from the dump valve at gear changes, sometimes, there is that rattlesnake type sound from the engine, that appears to be called either compressor surge,stall, wastegate chatter etc.

Either way, whatever it is called, the car doesn't always dump off properly and sometimes makes that chattering sound instead, it is temperemental, sometimes dumping off, sometimes chattering.

I have even tried another DV12 from a car that is working fine, to eliminate the possibility of a faulty dump valve, so it is not the Dump valve causing it, as I know some people say that the dump valve cannot be opening properly which would case that noise.

Some of you I know like that chattering noise, but I dont, and would rather the dump valve be dumping off properly instead of sounding lazy and making a chattering type sound.

APart from this the car drives faultless and doesnt seem down on power. I also have a boost gauge fitted which shows the correct boost of 15PSi.

ANy suggestions of possible problems that might be causing this, or If anyone has had this happen to them and knows what the problem is, please enlighten me, as it cant be doing the car any good.

AlanPPP

iTrader: (2)

Take it off mate! Bailey are well known for sticking.

Splitpin

As Alan says, it might be sticking, or it might simply be that it's set up in such a way (spring. preload) that it simply won't open when it "should".

Best cure is to take it off and put an OE Subaru valve on in its place.

ShaggyDooWRX

iTrader: (3)

Do you think that is all it is....

Would this be the case though, having tried two different DV12's, one from another car, that works fine on the other car?.....

Would there be any other causes

dunx

iTrader: (3)

It does little harm, and some of us like it.... using the softest spring possible, that doesn't leak under full boost may help.

I fitted a stronger spring to my VTA DV to avoid it operating round town, but the turbo has it's own bag of tricks i.e. "chatter"...

dunx

ShaggyDooWRX

iTrader: (3)

Replaced the vacuum pipe and now it is working properly!

Sorted

AlanPPP

iTrader: (2)

Good Good