tr VW ECU Up for sale is a Working, in excellent condition Vw Scirocco ECU. VW part number 321 906 263 B, Bosch part # 0280800042(043). This ECU came out of a 8V Scirocco, it should fit other models/years.This unit controls the fuel mixture of the K-Jetronic system through inputs from the o2 sensor & others. It primarially adjusts the mixture through adjusting the fuel pressure (at the extra in-line injector), though it also performs other functions as well. As always your best bet is to match the part numbers with the part you need. A faulty ECU can cause a whole hots of issues with these cars, including non running, and random cutting out (but usually it will re-start moments later). Also idle control & emission issues are possible (excess smoke or overheating caused by lean running). Hot or cold start issues can be caused as well. These units are no longer available almost everywhere and VERY hard to find used. If you can find a new one, they are usually in the $1000+ range. Ouch, not here! This comes with a 30 day warranty.