I have an 2002 1.9 TDI

What does the plastic 'thingy' do below the accelerator pedal, it screws of very easily (curiosity got the bertter of me) and i can press the pedal down further if it is romoved (haven't yet looked to see if it makes the car any quicker)

Any ideas anyone?

I dont think it serves any real purpose other than a stop so you dont put the pedal through the carpet.

I used to think it was the kickdown switch for the automatic transmission, until I discovered that it was fittend on ones with manual transmission as well.

I guess it's just a stop for the pedal, so that the drive-by-wire controller has a standard reference point for WOT (Wide Open Throttle).

ETKA lists a stop for accelerator pedal plus an escutcheon which fits on top. The part number is different for manuals and autos.

i'd call it a stop, and say it was to restrict the travel of the accelerator pedal... thinking about it the WOT idea makes alot of sense, i've heard the sensors for the fly by wire throttle systems can cause problems (ok this was ford) but putting something like this in place could / should restrict the problems by making sure the full throttle position was always the same.

On a car with the throttle cable you could in theory take this stop off and gain an inch or so in throttle opening capacity, if that makes sense...