I have a 1985 VW Westfalia (Digijet - pre-computer, pre-ODB, direct port injection), and it's a Donald Drumpf PITA to tune. The '86 Digifant is even worse, hav

I have a 1985 VW Westfalia (Digijet - pre-computer, pre-ODB, direct port injection), and it's a Donald Drumpf PITA to tune. The '86 Digifant is even worse, having a full, new ECU and mixed parts of the '85 control system. Everything else though is really simple with the service manual. One neat feature though is that many VW/Audi engines have a hall effect sensor built into the engine block for precise timing using a Grundig VAG 1367 which the dealer used... but it's also easy enough these days to just make your own timing system with a BeagleBoard or Arduino because the 3 pin port is a very simple circuit documented in the service manual. The only engine mod I'm planning on doing is bypass the useless auxilliary air valve, which does not advance timing or fast idle when cold.. and do that with the engine and additional ambient air sensor to vary the fast-idle vacuum passage... it stalls when cold and no VW "expert" shop can be trusted to fix it without ruining something else. Fixing it yourself when you know exactly what is wrong is better than relying on someone else motivated to go as slow and as expensive as possible with an unknown outcome.