I posted this on the wrong forum at first. I included a kind reply from that forum:
I have a 93 4-speed manual 2 litre. It started bucking, and my
mechanic thought it was the coolant sensor. He tried a new one, but
> that did not help. He thinks it's the engine computer. I asked him
> what else it could be, and he said only the wiring.
> The car starts, but dies. I have to crank it in first a few times,
> then sort of pop the clutch and rev it to get it going. He took the
> sensor out, and at least the bucking stopped.
> Any ideas? Does anyone know of a reliable source for a used or rebuilt > EC box?
> Engine computer :
> BOSCH # is 0261200874
> VW # is 8A0907404J
> VIN WVW ZZZ 312 PE 09 1221