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Discussion Starter #1
I am a tech for a shop that sees alot of VW cars. Two times in the last year we have had cars with this issue and chased them all over until we had to draw the line due to time and expense.

Symptoms are that the car will start out fine and drive normal for a minute or two, sometimes less, sometimes more, then during normal driving the throttle response will just go dead. No matter what you do to the pedal, the car does not respond, its as if you are not touching the pedal at all and the car will coast to a stop. It will only come back to normal after coming to a dead stop. Then you can start out fine again. If you floor it right off the bat it will you get up to speed but eventually the throttle response will randomly die again.

On two different cars I have run through everything I can with a snap on Verus scanner that supports VW/Audi. I have monitored everything I possibly can. There are the two corresponding throttle signals that are redundant, and one is basically a back-up to the other. They should read opposite, for example one at 80% while the other is at 20%. Sometimes this happens and sometimes it does not.

I have also run through all the online checks/tests and everything in ALLDATA. It all checks out fine as far as the pedal position sensor and throttle body actuator go. Continuity and resistance from both of those sensors to the ECU is also fine.

By the way there are no codes in the ecu on either cars.

At this point it seems replacing the pedal position sensor would seem logical, however I am hesitant to do so and incur that expense without something more decisive.

Given I have seen this twice, I would think others have as well. I just want to make sure there are no other issues maybe that are making it seem like a pedal position switch.

Let me know, thanks
 

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4,466 Posts
The throttle body position can be resetted with vag-com I believe. That can be a problem sometimes, I've never had the issue myself.

Which motor is it? Drive by wire I'm guessing 1.8/vr6?
Do any lights come on like the traction control light?
If this is the case and it isn't the throttle body position or sensor it could be some misreading in the traction control which would kill the throttle, which is this make of cars way of dealing with traction. It also cuts throttle when the ebrake is engaged, fun fact.

Since there are no codes I can't really jump to many more conclusions.
 

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Discussion Starter #3
no lights, no epc or cel

I do not have access to vagcom. U would think a $10k snap-on scanner would do the job.

I have went through the tb reset procedure several times and the scanner acts fine and says that the tb reset was successful but there is no change.
 

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MK4 & MK5 Owner
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8,444 Posts
Replace the throttle body. Don't use the snap on tool on vag cars. Spend the $250 and get vag-com. Being a shop that see them a lot it's a no brainer. I've used the snap on tools and they are basic compared to what vag-com has access too. If it's not the pedal, not the ecu then it's probably just a bad throttle body. The throttle position sensor is built into them and cannot be replaced separate.
 
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