Still got a ****** Boost Leak

[martinjs]

Sideways is standard.

Lee - I have mine the wrong way round as well - you get some chatter on gear changes with teh metal piston.

when i had mine in the vertical position (DV006) i did get the 'chatter' but couldnt get it to stop surging, got a new piston and a 'tuning' kit for it (a few different strength springs and shims) tried a stiffer spring (red) and a weaker one (yellow) but still surges, what colour springs are you using doug/lee, got it in the horizontal position at the moment with no probs but...i want my chatter back lol

martin

[Doug_RS2]

I use the standard spring - it has all been reconditioned but I don't get any surging and it held over 2 Bar no problem and 1.8 Bar at redline - the wrong way round.

I'd prefer it to chatter than to open slower with a stiffer spring - I will be fitting a second one just in case one seizes - I don't think it is good for the turbo if that happens.

[rotoryboy]

Quote:
Originally Posted by jameswkr
Dr H. Your wastegate pre load looks like its been played with. Are you sure this is set correctly ??


Yeah, good point there. I have spent the better part of 6 months trying to find a "leak" that was not there. In the end a good chap with a VAGCOM and some turbo knowledge diagnosed the wastegate "preload" as having been fiddled with. He returned it to factory spec and the difference in performance and drivability is remarkable. I'm not sure how it all works, but the chappie worked on the hex screw in the top of the wastegate and that's it. Worth a check if you can't find your "leak"

This was posted in "my clean engine" dont know if it helps

[Dr H]

Quote:
Originally Posted by jameswkr
Dr H. Your wastegate pre load looks like its been played with. Are you sure this is set correctly ??

Pretty sure it is but maybe a bit of a fiddle will help. The car used to be super chipped but that was removed before I bought it. I did talk to Paul N about WG settings as before I had the homefry the boost would peak up to 1.4 bar sometimes. Turned out the WG spring needed backing off. I'll check it again.

[Dr H]

Got Paul N's spare ECU today, fitted it and the car is STILL the same! It really does feel and sound like a leak

I disconnected the WGFV and the car makes 0.4 bar boost - correct?

I'm really at a loss now changed all the hoses and pipes, checked the WG diaphragm, tried different MAF, tried different ECU, tried normal fuel and optimax, new DV and WGFV, check WG mechanical only boost.

How do I check the lambda? It's only 7000 miles old and has never showed any problems.

Where else could a leak occur?

[Dr H]

Anyone? before I have a sleepless night

[martinjs]

Shouldnt it be hitting more than 0.4bar with wgfv disconnected leigh?

[Dr H]

Shouldnt it be hitting more than 0.4bar with wgfv disconnected leigh?

Yeah APNess just texted me the same thing. I'll check it again tomorrow and see what I get. If it is low what could be causing this?

Cheers

[audiman]

Would a split in the accumulater in the n/s inner wind cause a boost leakage problem? Isnt there a check valve that goes to the heater system? Would a hose to the diff lock cause a problem?

[audiman]

If thats low then turn the wastegate spring down! That is what controls mechanical boost. Set it to about 0.8 bar, that should be enough. Then reconnect the WGFV, and try again.

[Dr H]

If thats low then turn the wastegate spring down! That is what controls mechanical boost. Set it to about 0.8 bar, that should be enough. Then reconnect the WGFV, and try again.

Tom - I wind the spring down? Do you mean screw it further down i.e. make it tighter?

APNess just texted me the same idea but I bet you're not driving as fast as he is claiming he was when he did it!

[audiman]

Thats right, screw it in, make it tighter(oh er) You will want about 0.8 bar mechanical boost, that should do.

Have you pressure tested the system??? Or have you just chnaged things? Sometimes the clips dont grip tight enough and leaks occur at joints

[Dr H]

Thats right, screw it in, make it tighter(oh er) You will want about 0.8 bar mechanical boost, that should do.

Have you pressure tested the system??? Or have you just chnaged things? Sometimes the clips dont grip tight enough and leaks occur at joints

Pressure tested it before all the changes at Gregs meet. You were there but were a bit hungover so probably don't remember. Did it twice in fact!

Changed everything and the symptoms are identical so I did the clips up really tight - I even snapped one tightening it up

[S2central.net]

Got Paul N's spare ECU today, fitted it and the car is STILL the same! It really does feel and sound like a leak

I disconnected the WGFV and the car makes 0.4 bar boost - correct?

I'm really at a loss now changed all the hoses and pipes, checked the WG diaphragm, tried different MAF, tried different ECU, tried normal fuel and optimax, new DV and WGFV, check WG mechanical only boost.

How do I check the lambda? It's only 7000 miles old and has never showed any problems.

Where else could a leak occur?

That sounds a little low on the mechanical boost alright. If you are hearing a leak, then you most certainly have one - what about the intercooler ?

[Dr H]

Will check the mechanical boost again later. I had the intercooler off at Gregs meet and there was nothing to suggest any damage or leaks. Maybe I need to do some very selective pressure testing of specific components?

I can't see that it is the hoses now so what else could be leaking?

Intercooler?
Crossmember?
turbo?
EM?
IM?