Took intercooler off this morning to have it leak tested. First time I've had it off since shop had turbo off to change exhaust gaskets. Noticed oil residue at intercooler outlet (where it joins the manifold) and around the turbo outlet (at the turbo to intercooler pipe join). Signs of a failing turbo?

its normal to have a bit of oil residue in there

^^lhs...a bit of oil is normal.
But back to your original noise issue...I may have missed it in the posts but you have an aftermarket BOV, correct? So why don't you just put a standard one on and see what happens. The upside of this also is that a standard one will actually give you better performance...

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No Subarus currently owned

Yeah I know, but it's also $$$.

Some good and bad news. Had intercooler tested with the intake hose on. Revealed hose flange is slightly warped and leaking above 5psi. Hopefully that's the culprit.

Subaru want $350 for a hose! Is there anywhere else I can get one?

Thanks for the info re- oil residue.

i'd be looking for an aftermarket one if possible, will be a heap cheaper, i'm not that familiar with the early model hose setups though so just guessing now really good luck, hopefully its an easy fix

Any ideas where to look?

ebay?

is this the hose we're talkning about?

http://cgi.ebay.com.au/IMPREZA-WRX-S...item4ced2160e0

or this one:

http://cgi.ebay.com.au/IMPREZA-WRX-G...item4cebd3aa0c

http://www.japanesewholesale.com.au

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No Subarus currently owned

First one no, second one almost, but has no flange to bolt to intercooler, which is where the problem is (pipe's flange is slightly warped.)

No luck there, unfortunately. Though he did say he could sell an STI intercooler for $220 to which I could fit a silicone hose. That'd probably come to $350, which is what Subaru want for the plastic pipe alone! Pity I'm 5000km away in NSW!

Thanks lads.