Loss of power on 2001 vw passat

[Neil1974]

Hi ,
Wonder if any one can help, My vw passat seems to have no or limited power until the revs hit 2500rpm then it kicks into life below that it seems very slugish, any ideas or advice greatly appreciated.

[dewaltdisney]

I think that the Passat has a low pressure turbo and it sounds like this might be defective.

DWD

[Neil1974]

Thanks sounds like it could be expensive !!
Is it an easy fix

Neil

[dewaltdisney]

No, pricey I am afraid. What I would advise is find a cheapo garage that can read off the fault codes on the computer. They link the box on to the car and it will tell them where the fault is through the engine management system. At least you know where you are going. This is the sort of thing http://www.talktomycar.co.uk/products/c ... /mj004.htm or this one http://www.talktomycar.co.uk/products/c ... /mj002.htm

DWD

[kellys_eye]

Check for leaks around the turbo housing first. Burst hoses etc? Is there a waste gate - possibly stuck open. Exhaust system - free flowing?

Worst case is the main turbo shaft bearing is siezing in which case a refurbished or new turbo will be required.

[Raf]

which engine?

turbo will be the variable type (VNT) so the controller for the vanes may be knackered (cheaper fix), controller will either be vac operated (is so check vac lines and any vac reservoir it may have, there will also be some kind of pressure control valve that controls it.) or electric operated = new controller (if it is that).

vanes can also be jammed because of the gases involved, this either means a new turbo or you can strip it down and clean them up. i prefer strip down and clean; cheaper and not difficult.

see this vid
http://www.streetfire.net/video/variabl ... 191918.htm

if yours are stuck in the open position then it wont spool up fast enough at lower revs as their isnt enough energy.

however if the turbo is spooling up and giving the right boost at the higher revs then i should think the shaft and fans are okay.

i would plug it into VAGCOM first though; if you find someone with a decent version they can check actuator movements....

hth

p.s. check the actuator arm too; had a beemer where the circlip holding it on snapped.

[welshgar]

if the car runs fine otherwise, i'd check the MAF unit first, common problem on Vw's

Also is it diesel or petrol??

if diesel it could be a blocked/clogged EGR valve

if Petrol it could be a sticking inlet flap.

Neither are hard or that expensive to check/clean.

If those are fine, boost pipes and lastly the turbo would be there to check.

HtH

Gar

[Raf]

easy way to check MAF is to unplug it; ecu sets fuelling/air mix to default settings. if it runs better then maf is dodgey.

they can be cleaned (hit and miss); use non contact elec cleaner and be very gentle.