What is a VNT on a turbo and anyone know how to clean it?

[VAGMAN1]

keep on reading about cleaning this part on the canadian website tdiclub.com, but can't work out exactly what it is and confused by some of their terms!

lots of people saying they can become sooted-up and sticky, so best to clean but how?! is it a big job?

 

[RichA3Turbo]

http://www.honeywell.com/sites/ts/tt/Pas...12155701757.htm

 

[chrisb]

Have a look at http://www.technologie-entwicklung.de/Gasturbines/VNT15-Turbo/body_vnt15-turbo.html

You'd have to take the turbo off.

However, if you think the mechanism is sticking, you can work it back and forward from under the car, which might help.

 

[chrisb]

Incidentally, if you go to a dealer and it's sticking, they will willingly change the turbo for you at £1000+.

 

[VAGMAN1]

what am I looking for, in terms of the rod which needs working back and forth? do I have to remove anything to get to the rod?

 

[chrisb]

Get the car on ramps and remove the undershield.

Lie under the car, and look upwards at the back of the engine. You should see the vacuum unit below the turbo & exhaust manifold- it has a vacuum hose running to it from the N75 valve on the bulkhead. Attached to the vacuum unit is the VNT mechanism. Pull it downwards, and let it go back up. Mine was pretty stiff to move, even though I've never had any problems.