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varicosewayne
27-04-2009, 04:33 PM
Hi I have just moved on from having a mk2 16v and now have an a3 quattro sport.

I have noticed that it over revs between gear changes and have been told this is due to the fly by wire throttle control. Does anyone know of a solution to this problem, I would much appreciate advise. thanks

SEMKY
27-04-2009, 10:41 PM
Hi Mate,

Suffering the same issue with mine. Has been diagnosed by several to the clutch pedal switch...seems to fit being that I had a new clutch pedal and cylinder replaced by a non specialist and the clutch pedal switch ain't there anymore.....have been away at sea since then so I haven't had chance to get it sorted, and either prove/disprove the theory.

I am hoping that this is the issue anyway....quite sure there may be other answers though.
Good luck!

varicosewayne
28-04-2009, 09:34 PM
Oh ok that sounds posible, suppose it gets the revs down quicker when it knows the clutch has been ingaged. I just thought thats how the car was ment to be:confused:

Cheers for the info mate, i'll look into it. (let me know if thats the problem on yours)

Crasher
28-04-2009, 09:37 PM
The clutch pedal switch tells the ECU you have pressed the clutch so the revs drop faster, it is a common failure and can be checked in Measuring Blocks 08 if you have access to diagnostic equipment.

SEMKY
29-04-2009, 12:05 PM
Nice one Crasher!

Will be checking it this weekend hopefully and will report back! Fingers crossed!;)

varicosewayne
30-04-2009, 04:55 PM
yea thanks crasher, will have to take it to my mate at kwick fit and whack it on the machine:beerchug:

varicosewayne
01-05-2009, 10:13 PM
yep put the car on the tester and sure enough it came up with the p1539 clutch switch improbable error. got the switch coming, probably sort it monday. thanks again.

SEMKY
03-05-2009, 08:51 PM
Nice one! Didn't manage to get home to do mine this weekend...hopefully will be the same thing on mine!;)

SEMKY
19-05-2009, 04:58 PM
Right then, I have been hooked up to VAG-COM at Votex, no fault codes were stored, but I still have the over-rev, and still can't see a switch where the drawing says it should be! Were all S3s fitted with a switch? Would bypassing the switch in some way prevent a fault code being registered?

Any thoughts gratefully recieved! :1zhelp:

Crasher
19-05-2009, 05:27 PM
The switch is on the bracket above the pedal, if you can’t see it that may be the problem!

zollaf
19-05-2009, 05:31 PM
the switch may be still attatched to the wires but tucked up somewhere, thus no fault codes as the ecu thinks its still there.

Crasher
19-05-2009, 06:39 PM
That is exactly how it was on TDIborasams’s car, it was tucked down the side of the centre consul.

SEMKY
19-05-2009, 08:21 PM
Hey thats great, thanks both!! I will have a more in-depth hunt around under there for a switch looking redundant!!

Cheers very much!!!:beerchug:

SEMKY
24-05-2009, 06:11 PM
Evening all...hope we are enjoying spectacular bank holiday weather...anyway, I just found my clutch pedal switch tucked neatly away just where Zollaf and Crasher suggested it may be....so I fitted it to no avail, the over-rev still existed.....bugger.:(
So measured the switch with multimeter and its open circuit in the clutch 'pedal up' position, and closed circuit with nr 0 resistance when pressed.......to me this seems right?

Do I need to do anything to 're-activate' like a ecu reset or should it work straight away?

Any thoughts either way guys?:confused:

Crasher
24-05-2009, 08:30 PM
You need to see if it is working in Measuring Blocks.

SEMKY
25-05-2009, 07:41 PM
Ah ok cheers Crasher....Have just got my version of VAG-COM to work, but have only had a brief look so far...
Where would I find the measuring block for this....in the clutch section, or somewhere else?
Cheers again!

Crasher
25-05-2009, 09:19 PM
It is in Measuring Block’s 08, Group 066 Display Zone 2 a group of four 0’s i.e. 0000 that go 0011 with the brake pedal depressed and 0111 with the clutch depressed or 0100 with just the clutch depressed, the first digit is irrelevant.

SEMKY
25-05-2009, 09:57 PM
Sir, you are a legend!!! Many many thanks again!!!!!!!!!:beerchug: