Dead Gas Pedal Question

[martini]

cant change the title.... by dead pedal I mean dead gas pedal, not the one one next to the clutch...
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So my neighbor has a 2004 A4. He came to me today saying that he gets an occasional dead pedal - press the gas, get nothing. Hes an automatic.

I asked if the engine rev's, he says it doesnt. If he lets the pedal back up, then down again the car will go. Claims it is worse in hot weather.

I've been around the a4 scene for a while and thought I knew a decent chunk...never heard of this...

any clue? pedal sensor or something?

no codes at all. brought it to the dealer, they couldnt find anything. He had the throttle body replaced on a whim.

[AudiA4Turbo22]

defective Drive by wire system?

[absolutegtr]

Throttle body already replaced.....I would assume the the next "logical" thing next is the actual pedal assembly itself that is malfunctioning

This is a question for diagnosticator

[AudiA4Turbo22]

Diagnosticator and A4TL especially Old Guy are the Shit!

[F16HTON]

Have him check to see if his brake light switch it malfunctioning.

[martini]

Have him check to see if his brake light switch it malfunctioning.

care to explain this one.... i read somewhere about this... but couldnt connect how this could cause dead pedal

[F16HTON]

Has to do with the DBW system.

There is logic in the Engine Control Module that, under certain cirucmstances will not allow throttle when the brakes are applied. A faulty or sticky brake switch is typically the culprit.

[Dos::Avants]

care to explain this one.... i read somewhere about this... but couldnt connect how this could cause dead pedal

I believe this is a safety to prevent throttle operation inadvertently while braking, especially while in gear. So, if the ECU is sensing that the pedal is being activated via the faulty switch, then it won't allow the throttle to operate since it is throttle by wire.

[gtimart]

Aha, felt that once when I wanted to try building boost before being able to accelerate, like race cars do on a restart
I don't want to hijack the thread, but I'd certainly be interested in knowing if this can be disabled...

[F16HTON]

Aha, felt that once when I wanted to try building boost before being able to accelerate, like race cars do on a restart
I don't want to hijack the thread, but I'd certainly be interested in knowing if this can be disabled...

Nope