B5 S4 boost leak maybe?

[andybnwc]

Hi just been fixing a chewed through washer pump cable due to driving the car with no arch liner in lol

In the process i noticed some oil spray onto the bottom intercooler hose in front of washer bottle , could this be the reason for the maximum boost exeeded error and momentary limp mode if WOT particulary in higher gears ive posted before and checked pretty much everything with a pressure tester and n75,dvs,all pipes etc apart from wastegates on turbos because
i cant get to them lol

Please see pics

 

[Blue_Thunder]

Yup, that's a boost leak. Get it pressure tested. The oil will have been forced out by the pressurised air. Don't go WOT until you get it sorted!!

 

[andybnwc]

I have already presure tested and didnt find any leaks im wondering if i didnt use enough pressure i will try again with a garage airline rather than my noisey 5 litre compresor lol

 

[Blue_Thunder]

You need to pressurise up to 15psi. Don't go any higher than that as you can cause damage.

 

[andybnwc]

I will have to try again see what happens

 

[Markey]

Is there any oil round the bottom of the pipe or is all just over the IC ?

 

[shineydave]

i'd suggest that it isn't a big enough leak to cause a max charge pressure exceeded fault but as Blue Thunder says it certainly needs investigating as these things rarely fix themselves, i've come across 2 intercoolers recently that were leaking oil and neither threw a code so you may have another problem as well.

could just be it needs the hose clamp tightening.

when i do a pressure test i use the tyre on the car as a pressure source as it's silent so you can hear the leak, just keep pumping the tyre back up. a one way valve in the airline helps also by stopping the air leaking back out.

 

[andybnwc]

thats a awesome idea , im gonna do that instead , will this check the wastegate lines too

 

[Blue_Thunder]

The wastegates on a turbo are on the exhaust side, so you won't be able to pressure test that. You should run some vagcom logs on Block 115 to check your specified and actual boost. If the actual is significantly lower than actual, it's possibly a problem with the wastegates or N75.


Not too sure you can actualy check the wastegates without removing the turbos.

 

[andybnwc]

I dont have much free time is there anyone in the northwest that you know of who could check and fix the problem?

 

[shineydave]

i'd agree with that, i can't even see the damn turbos without the aid of a mirror.

 

[shineydave]

PM Grizz on RS246, his garage is in the Wirrell somewhere, he may be able to help

 

[andybnwc]

ok thanks i will do that ,its only held full boost for about a month out of the 5 years i owned it because of numerous boost leaks , egts,mafs,n75s etc lol