VW Golf GT TDi MK5 07 - Throttle actuator gone again!

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Wed 4 Jan 2017 18:16
VW Golf GT TDi MK5 07 - Throttle actuator gone again! - Alan Townsin
Hi all, recently replaced my throttle main body after checking the error message that came up with the engine warning light. Light was cleared and all worked fine for the last month. Today it had come back in with the same symptoms of an engine over run when turning the car ignition off. I'm guessing it's exactly the same problem but am scratching my head as to what has made it go again?!

I also have the infamous traction control light on constantly and yet there is no code showing with this on the reader that read the code for the engine fault...... dashboard is like a Christmas tree!!!! Fingers crossed someone can help.

Many thanks!!
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Wed 4 Jan 2017 19:39
VW Golf GT TDi MK5 07 - Throttle actuator gone again! - elekie&a/c doctor

Was the throttle body a genuine part?I would check power supply to it.Fuse is in the engine bay fuse box.Any faults logged will be able to be read with adequate diagnostic equipment.Most of the xmas cracker fault code readers are not good enough.

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Wed 4 Jan 2017 19:58
VW Golf GT TDi MK5 07 - Throttle actuator gone again! - Railroad.

Throttle actuator? What throttle actuator? Diesel engines don't have a throttle, let alone a throttle actuator. Could you be confusing it with the anti-shudder valve? It's located in the air intake and looks like a throttle, but it has nothing to do with engine speed control.

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Thu 5 Jan 2017 10:26
VW Golf GT TDi MK5 07 - Throttle actuator gone again! - dieselnut

I thought most diesels fitted with a DPF now had throttle valves.

It is partially closed during a regen to keep the temperature high in the engine/exhaust.

Also acts a s an anti-shudder valve on switch off as mentioned above.

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Fri 6 Jan 2017 12:34
VW Golf GT TDi MK5 07 - Throttle actuator gone again! - Alan Townsin
Yes the anti shudder. Was going on what the reader was saying in terms of 'tech terms'. As you say it did shudder as the engine was turned off, but in last couple of days it hasn't. It shuddered after a couple of short journeys then the light came on. I've cleared the light now and it hasn't shuddered since so it's staying off. Think I'm going to change the egr valve as I read somewhere that doing one with out the other doesn't always do much. Sound right?
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Fri 6 Jan 2017 12:31
VW Golf GT TDi MK5 07 - Throttle actuator gone again! - Alan Townsin
Thanks for the reply. The scanner is a Vgate scanner and has brought up the following code. P2108 throttle actuator performance. I cleared the code and it hasn't come back yet after a couple of days. I think I will be changing the egr valve as I didn't do this before, hopefully this will help? Checked fuses, all ok.
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