Poor performance

[rob160]

Long story short sort of.
I have a A4 1.9 tdi 130 on a 2002 plate with 235000 miles and its been down on power for over a year.
I borrowed it to a customer for 2-3 weeks and when I got it back there was no boost and going into limp mode with a over boost code on motorways. I stripped the turbo and cleans the vains and hay presto I gradually got power back over a few days.
It feels more like 100 bhp so I want to get to the bottom of it now.
Things iv done are.
Cleaned the vains
Cleaned the EGR and manifold
Replaced vacuum elbow on boost sensor.
Silicon sealed the vac pipe on the tandem pump.
Next job is to strip the turbo again.
Oh when I first start the car and pull off quickly there no boost wile either the vacuum builds or the vains unstick, that's what I think.
Sort to go on but any ideas would be great.

[rob160]

Any 1

[Doctle Odd]

Can you scan it with VCDS and post the results? There's a bunch of reasons why these cars aren't boosting some cheap some not. Scan first

[zollaf]

get an assistant to start the car while you observe the boost controller above the turbo. it should move up under vacuum as soon as the car is started.

[rob160]

Yes it does but I'm unsure if it moves enough.

[zollaf]

19 mm is how much it should move. if its not 19, it very close to 19. anyone confirm 19 or be more exact ??

[adamss24]

It could be a boost control valve or the MAF. I would discount the turbo IF you cleaned it properly before...

[rob160]

Will check it out in the next few days hopefully

[rob160]

Had the battery tested and its 86% good. Got to be the starter.

[rob160]

Sort wrong tread ha ha