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Old 3rd July 2019, 09:11 PM
HPsauce HPsauce is offline
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Join Date: Sep 2011
Location: Chilterns, almost over HS2!
Posts: 8,366
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I know it's a D3 not a D2, but a problem I (and others here) have with some of our D2s is serious lack of power, accelerating very gently and holding gear changes back. Typically after stopping at a junction (sound familiar?).
This is caused by a very tiny maladjustment of the brake pedal switch which actually has two switches internally; I wouldn't be surprised if the D3 was very similar.

One switch basically operates the brake lights, the other informs the ECUs that the brake pedal is depressed. There is a tiny bit of movement between the two actuating and it is possible to release the brake pedal, removing brake pressure and turning off the brake lights yet still telling the ECU the pedal is being pressed.

It's possible to see this happening very easily by monitoring the relevant channels with VCDS and gently operating the brake pedal. It can be even more obvious with the engine off as there's no servo to magnify foot pressure.
On my S8 this would typically occur after a gentle stop, with the brake pedal only depressed very slightly and released softly. After a heavy braking it would spring fully back and both switches would change effectively together.

The D2 solution is to adjust the brake pedal switch by screwing it in the appropriate direction. Bit of a swine to get at but do-able.

I know many later Audis (and other cars) have "set once" brake/clutch pedal switches with a very specific installation procedure so that may not be an option on a D3, but VCDS could still be used to check how sensitive they were and if they ever "stuck".
__________________
2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions, ski hatch retrofit; extended leather. Aftermarket DVB-T, reversing camera and full XCarlink (Bluetooth etc.).
2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation". (A much rarer model than a D2 S8 by the way!) Oh, and a brand new engine at just under 30,000 miles on the factory one!
Finally: gone, but not forgotten.....
1998 D2 PF S8. AgateGrey/Platinum. Every option (I think) except electric rear seats, tiptronic steering wheel, ski hatch, towbar & dimming door mirrors.
e.g. Cruise control, NavPlus/TV, Bose, GSM, Xenons, Solar roof, Parking sensors, Alcantara/leather everywhere of course. (internal dimming mirror added later)
1998 (very early) Ford Focus 1.8 Zetec; ABS/TCS, Heated screen/mirrors, Aircon, Auto-dim mirror, Leather, Trip computer, Cruise control, OEM Ford SatNav with CD changer.
And before that a lot of Rover 800s, a few oddities, a lovely Triumph Dolomite 1850HL with Overdrive and way back in my schooldays an Austin Seven aka Mini 850!

Last edited by HPsauce; 3rd July 2019 at 09:14 PM.
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