Throttle body?

[willg60]

Hello again....! Still having trouble with the S. I can hear you all saying, here he goes again! Will, with his missfire/dodge gearbox/whatever it is!

Anyway... the MAF obvioulsy didn't work, cos it's still the same. Weird, cos it seemed ok initially after it was fitted, but now the problem is coming back, gradually getting worse again. I tryed disconnecting the battery today for a couple of hours... made no difference. I keep thinking about it and testing it seeing exactly when it occurs. If it was a mechanical fault, surely the MAF change would have made no difference? and also it still hestitate/judders when it tip mode. One thing that is for sure, is that it only occurs on about 10% throttle.. and not on full or just a tiny bit. Happens more when conering slowly and more when the engines hot.

Because of the thump, I think it's mechanical, something with the gearbox, but then as I said before, when they changed out the MAF, initally, at least for a day or two, it was fine.

The ECU was changed not that long ago due to water ingress - the TCU is in the same comartment, right? maybe thats got water damage?

Lastly... my latest guess is the throttle body? seeing that the position of the throttle is paramount to the problems occurance, could it be something to do with the throttle body itself? electrics?

Just guessing, but then thats all thats left to do, as two trips to the stealers has resulted in me paying a grand for two things I didn't really need. Plus their vagcom did not leave any fault codes whatsoever...??

Sorry to keep going on, I'm at a loss and I can't sell on a car that I know has a problem.... and I'm worried I'm damaging it whilst driving it like this...

Help !!

[Ska]

did you change those coil packs and spark plugs in the end? The TCU sits on the lhs ( has a ZF number on it along with a Bosch number and Audi part no.) when facing the car in the same box as the ECU on the rhs look for water marks around the inside of the box.

[cruiser647]

Not sure, but there are a few things I would do here. They are:-

clean the throttle body/butterfly valve with alcohol and a cloth, and spray in plenty of carb cleaner.

Nice and easy and worth a try.

[charlie61]

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clean the throttle body/butterfly valve with alcohol

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I doubt if Will has any alcohol left in his house

[willg60]

Just replenished the fridge !! You're right though, car is stressing me right out !! I just don't know what to do next, got a week off work, but it's pi$$ing down with rain.... doh !! Need to get out there and get my head under the bonnet... Not sure I will be more effective than Audi's diagnistic equipment though??!

[SneakyMcC]

[ QUOTE ]

The bodies are going out of calibration. This can cause poor drive-ability and poor idling.

Common symptoms:

- stalling at traffic lights

- cutting out under power

- in extreme conditions fault brings engine management light on.

If in any doubt BBA can arrange a test hire. Please call 01634 230055 for more details.

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From: here

PaulW posted this site on another thread...

Plus:

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Audi A4 Throttle Body failing for two reasons:

- Lack of power/jerkiness on small throttle opening

- Incorrect idle speed/stalling

BBA can supply remanufactured throttle body with a two year warranty.

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From here.