110 TDI VNT actuator

[nathanjuk]

Hi,

I have a 1999 Golf TDI 110 with the AHF engine and I've been having the old limp home mode problems due to the following fault code:

17958 - Charge Pressure: Control Deviation
P1550 - 35-10 - - - Intermittent

I have replaced all the vacuum hoses, the MAF, cleaned the VNT mechanism with the Mr Muscle trick and checked the N75 valve all with no success. Today I decided to check the actuator on the turbo after reading something about them failing. I disconnected the vacuum line to the turbo from the N75 valve and sucked on it. There was no resistance, the actuator didn't move and I got a mouth full of grit! I assume this means that the diaphragm in the actuator has gone.

I have looked on ETKA and found that the part number of the turbo is 038 253 019 c and a quick google search suggests that it's a garrett turbo and the actuator is garrett part number 434855-0015. I understand that it's not available from VW as a separate part. A quick ebay search found these:
Genuine new original manufactured by GARRETT turbocharger actuator VW Audi 1.9 | eBay
BRAND NEW ACTUATOR TURBOCHARGER VACUUME 1,9TDI 90HP 110HP AUDI VW 1,9TDI 2,0TDI | eBay

Can anyone confirm that they are they correct parts? Anyone have any advice on whether my diagnosis is correct or any other tips?

Thanks

[zollaf]

if the diaphragm is split and there is no resistance, then the vnt will not be activated and there will be no turbo at all, which would be very noticeablle as the car would have very little power. are you sure you are sucking on the right pipe ?
welcome to the forum.

[nathanjuk]

Thanks for the quick reply.

Yes the lack of power is very noticeable although I've had this problem for ages so I'd got used to it. When I got the car a couple of years ago I could overtake other cars, now I wouldn't be confident to overtake anything even when it's not gone into limp home mode. There is a difference in power when it goes into limp home mode so I assume that does more than just cut the boost.

I'm sure it was the correct pipe as I fitted it. It definitely goes to the actuator on the turbo.