Diagnostic Tools for 20V 7A engines

john at westcoastgarage.net john at westcoastgarage.net
Sat Nov 1 12:46:00 PDT 2008

You asked: 
"My better half offered to buy a diagnostic tool as appreciation for 
keeping her 1990 90 20v on the road.

Two options I found are Versatile Automotive Diagnostics (VAD) and 
Ross-Tech. Neither show the 20V engine on their compatibility lists. 
Ross-Tech said only 20V turbos from 1990 would work, and VAD was unsure 
and non-committal. I've found two plug-ins under the carpet on the 
driver side.

Does anyone have experience using a diagnostic tool with this engine?"

While VAG-COM works on my very early production sedan, I've been unable 
to get it to work on some others.  It won't be of much help anyway, as 
it only slightly elaborates (gives you words that describe what the code 
is) what you can get pulling the blink codes with a home made 
retriever.  I have VAG-COM as part of my toolset for day to day work on 
VAG vehicles, but its usefulness is pretty restricted on cars older than 
the mid-90s.  I think buying any diagnostic tool for use on a 7A 
equipped car would be a waste of your money.


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