Damp DV but is it dodgy?

[daisydave]

Hi all, don't post much on here as I'm more of a aircooled boy with a bay but have had my gti for about a year now and tbh I have grown quite attached :) Recently I have been hearing a faint hissing when the boost comes in and a blow off noise when I lift off the throttle almost like a dump valve :/   I also seem to be down on top end power like I'm down on boost.

I have done some research and been under her today and have found some oil collecting around the intercooler inlet so have cleaned the seal up and ordered a set of new seals to replace then all.

I also took a look at the DV valve as I was pretty sure this was the culprit and found the connector swimming in oil, if there is oil passing it surely so will air??  so I have ordered a new valve.

Just wondered if you lot thought this sounds about right or if there is other things I could be checking for?

Also the car is an 05 dsg and is totally standard.

Cheers

[GrayMK5GTI]

If you have oil on it there's a very high chance the diaphragm has split and spitting out air & oil 

At least it's a cheap fix 

Intercooler pipes always end up leaking, your best off buying the small pipe connector

Graeme

[daisydave]

Coolio cheers but small pipe connector? Do you mean the seals on the actual boost pipe, if so that's what I have ordered :)

[GTI5]

Hi all, don't post much on here as I'm more of a aircooled boy with a bay but have had my gti for about a year now and tbh I have grown quite attached :) Recently I have been hearing a faint hissing when the boost comes in and a blow off noise when I lift off the throttle almost like a dump valve :/   I also seem to be down on top end power like I'm down on boost.

I have done some research and been under her today and have found some oil collecting around the intercooler inlet so have cleaned the seal up and ordered a set of new seals to replace then all.

I also took a look at the DV valve as I was pretty sure this was the culprit and found the connector swimming in oil, if there is oil passing it surely so will air??  so I have ordered a new valve.

Just wondered if you lot thought this sounds about right or if there is other things I could be checking for?

Also the car is an 05 dsg and is totally standard.

Cheers

Oil on the DV is possibly a sign of your breather system letting by. The early PCV valve systems were prone to failure and there has since been a few revisions.

Did you have any splits or tears in the DV rubber diaphragm?

[daisydave]

I never took it off as I was running out of time and as there so cheap I thought I would change it as a matter of course being that they do appear to be a bit of a week link.

I have checked the PCV system by undoing the oil filler cap whist running and the revs dropped as they should or is there other things I should be looking for?

[GTI5]

I never look it off as I was running out of time and as there so cheap I thought I would change it as a matter of course being that they do appear to be a bit of a week link.

I have checked the PCV system by undoing the oil filler cap whist running and the revs dropped as they should or is there other things I should be looking for?

I would physically remove the Front PCV and inspect the valves.

[daisydave]

Ah ok, what I'm I looking for just worn split seals and diaphragms?

[GTI5]

Ah ok, what I'm I looking for just worn split seals and diaphragms?

http://changegears.wordpress.com/2011/08/18/g-revision-pcv-valve-internals/

[GrayMK5GTI]

Coolio cheers but small pipe connector? Do you mean the seals on the actual boost pipe, if so that's what I have ordered :)

IIRC it's the pipe from the discharge pipe to the intercooler that leaks, it's only a small section of pipe (20cm ish)

[daisydave]

Well replace my DV today aswell as some boost pipe seals, this is what the valve was like so please a looked Ito this!
I'm surprised at the difference, it's not just better than before I noticed the noise it's better than ever. A lot better throttle response and the car takes off now it's like having a new car :)