TDI deisel engine loses power intermittantly &.

Tiny
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  • 2003 VOLKSWAGEN JETTA
  • 89,000 MILES
Tdi deisel engine loses power intermittantly & engine light comes on at same time-diagnostics says engine overboost-What could this be & will it be expensive to fix-thinking it could be some sort of sensor

Friday, November 9th, 2012 AT 3:41 AM

8 Replies

Tiny
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The turbo vanes are stuck and need to be freed-up.

The vanes are vacuum controlled. Vacuum applied = more boost, no vacuum applied = less boost.
Carbon deposits build-up around the vanes and restrict their movement.

Here's a video of me working the vanes back & forth to free them up.

Thomas
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Friday, November 9th, 2012 AT 5:25 AM
Tiny
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Which TDi engine do you have? ALH or BEW?

There are differences in design & control. I'm assuming yours is an ALH.

Thomas
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Friday, November 9th, 2012 AT 5:26 AM
Tiny
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Forgot video... http://www.youtube.com/watch?v=uK9dFNS-ddM&feature=plcp
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Friday, November 9th, 2012 AT 5:29 AM
Tiny
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I presume that you are referring to the waste gate? I was curious so I had a look at your video, it looks like the waste gate control you are freeing up, is this so?
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Friday, November 9th, 2012 AT 6:26 AM
Tiny
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Actually not a wastegate... a wastgate dumps exhaust before the turbine so that the turbine does not spool-up or stops
spooling-up.

The Variable Vane Turbo uses an actuator rod / pod that repositions the vanes ahead of the turbine wheel... a narrow
passage through the vanes causes quicker exhaust flow to hit the turbine... spread apart vanes cause the exhaust to
hit the vanes at a slower speed.

http://www.youtube.com/watch?v=Gc2awh0O0Bc

Thomas
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Friday, November 9th, 2012 AT 3:17 PM
Tiny
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OK, don't do a lot on Vw's always like to learn something new, even after all these years I still will ask questions myself, thanks for the info.
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Sunday, November 11th, 2012 AT 12:44 PM
Tiny
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Had a TDi in yesterday with the same problem. 20min of working the vanes back & forth and all is fine again.

I wish people who asked questions would reply with a follow-up!

Thomas
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Sunday, November 11th, 2012 AT 5:38 PM
Tiny
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I find that if you get about 1 in 10 following up your doing well, not much you can do about it, just hope that you have fixed their problem and move on to the next one!
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Sunday, November 11th, 2012 AT 7:41 PM

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