Hello VWOC.
I have a red and black Golf GTI daily driver in north Texas. The TPS switch plastic housing has cracked and it had a erratic signal.It also somewhat disintegrated around the opening for the TB shaft .
I tried a new TPS from a same year Cabriolet 1.8 (because it was available) and at about 25mph to 30 mph it stumbled until I took my foot off the pedal. It retarded my timing too much and It only worked from 0-25 mph . I tried the Michigan based PartsPlace mentioned on this forum for a new TPS, They didn't have one either.
VW no longer has availability. I have submitted a locator part request on Car-Parts.com for the entire Throttle Body and TPS combination.but no reply . Could just feed .45 volts into the yellow wire full time.
If I go with an alternative part, then I may need access to a Bentley Schematic. The car was made in Mexico.
Advice is appreciated.