Also, VW,AUDI never released aftermarket OBDII interfaces within 3 years of model years to repair shops other than their dealers. GM, FORD, CHRYSLER were only about a 6-9 month delay. Diagnostic codes could only pulled pulled by the VW dealers.
Are you absolutely sure about that? I always make sure, when we buy a new vehicle, that I have a code reader for it, all the way back to to OBDI. We just donated a VW Passat a couple of years ago we'd had since 2003, and I could swear I had a OBDII reader for it almost immediately. I believe in knowing as much as the stealer. I've had two dealership shops, one Mercedes and one Dodge lie to me in instances which could have cost me and mine lives. Believe it or not, when I had a fairly new Dodge Caravan (fit the family situation and popular at the time), the cable from the lever to the transmission broke. Whereupon, I put it up against a wall, selected "Drive" and pulled on the broken off cable until I felt it work through the gears and engage in "Dr." I clamped it there right at the transmission with vise grips. I then drove all the way out to the dealer and they claimed the cable wasn't part of the "drive-train" warranty. Faced with suit, they caved. (I think they would have even caved before present day arbitration.) Same bunch made the same claim when a hub drive lug bolt broke off. Caved on that one too.
The worst though was the Mercedes. I kept having alternator problems - wearing out belts etc. Finally, I climbed under and saw that the fixing bolt on the mount was undersized; alternator body literally rattling around. When I confronted the mechanic, he confessed that the shop manager wouldn't let him order the proper sized bolt, $17.50 at the time, more now with inflation. When I confronted him, he tried exploding at me. When he got through, I told him I was preferring criminal charges and his attitude changed. That tactic might not be quite legal, but it worked. He had already caused me extreme difficulties, with the car going dead on I-59 at the Hammondville exit, stopped by local cops because my headlights were almost gone. A diesel, once started will run until out of fuel. However, the alternator couldn't recharge the battery. Around that time, I decided I needed to know as much as the dealer. I'd always worked on cars, but EC modules were new to me...