AGU performance issues.

[xxChrisxx]

I'm having some issues. Car's just rolled over 121K, everything is standard and pretty well maintained. No smoke, doesn't use any oil, compression on all cylinders is good.

Symptoms:

Painfully slow.
Throttle response is awful.
Whistling whilst spooling up and 'on boost'.
Turbo surge (fluttering) even though the DV is fine.
Smells slightly rich, but not enough to give a failed lambda reading. (spark plugs have very slight carbon fouling).


It hard to describe but the throttle has no 'resistance'. It used to have a steady acceleration as you progressively opened the throttle. Now nothing at all until the throttle is fully open (and then still nothing). I have noticed there there seems to be a small amount of oil in the breather pipe. My gut says a hole in a pipe somewhere, but short of taking off every single pipe I can't find one. Are there any common pipes that split?

Any ideas would be appreciated.

[daz veedub]

check all boost pipes

clean throttle bodie

have u scanned for any fault codes

[rio_gti]

clean throttle body out for starters,

check all oost pipes but also pipes to n75 valve, also wires to n75 valve as it might not be working properly

what dv is it??

try and get someone with vagcom to scan it, and log to see you may have a failing maf,

[xxChrisxx]

I had the throttle body off for a clean not long ago.
Though I've had a cursory look at the boost pipes, i'll have to take them off and inspect one by one. Unless anyone has a lazyman's method?
I suspect this is acutally the problem, but taking off each one is a total faff.
Everything on the car is OEM, or decent alternative. The Bosch valve works fine.
It's been tried with a known good MAF and is exactly the same.

I'll try to get it scanned sometime soon.

[daz veedub]

if all pipes are standerd am guessing 1 has perished or spilt 

[sprout99]

MAF??

[rio_gti]

when you say there is no go in it, do you mean that it will only do a max of somethin like 30 mph?? if so the cat may have collapsed 

how do you know the dv works fine??

[xxChrisxx]

when you say there is no go in it, do you mean that it will only do a max of somethin like 30 mph?? if so the cat may have collapsed 

how do you know the dv works fine??

Nah it's nothing catastrophic. It'll still go and sit happily at motorway speeds, it just doesn't accelerate on sliproads.

DV works fine becuase it's been tested with one that is known to be good.

[gavgtiturbo]

my moneys on intrcooler pipes,boost pipes or breather pipes

[Ant1981]

I wonder if there's a diagram of the boost pipe system?