Yo, does anybody know where the diagnostic plug in on these Audi V8's for checking out the engine management? Mine's a '91 RHD V8 auto.

Ta

Hello Richard!

You can find the pins for reading out the ECU under the right floor covering (passenger side). To use this interface you'll need a VAG 1552. The V8 has no onboard diagnostic with flashing LED like GM e.g.

For more information take a look at www.baumtools.com or http://www.opendiag.org/.

Maik

Check out http://www.sjmautotechnik.com/ecufv8.html.
The page lists all fault codes and explain how you can check/clear them by using a LED and a jumper wire. The connectors are located behind the carpet in the passenger footwell.

Hallo!
If you learn Swedisch you can build your own Interface with info from this site: http://home.swipnet.se/fredde-b/ Come on, its not so hard, kids speak it here.
Ok, here it is in English: http://www.planetfall.com/~jeff/obdii/
Then you only have to download the Sw demo from this site: http://www.ross-tech.com
And Voila! Your are your own diagnostic master!
Best of all it works! Its cheap ~20 EUR for the printed board and ~40EUR for the components. (the special connector for the car is a little bit on the expensive side but you can make it without it.)

Hi Stefan,

the Sites you recommend in this thread include many information about building
your own Interface but some information unfortunately is missing. As we all
know the V8 does not have a OBDII Connector for diagnostics. There are four
two-pin connectors in the passenger footwell, but how do I have to connect all
these pins to the SUB-D connector on the interface?

Do you know anything about this?

Hi!

You only need to connect to 2 of them, I think it is the 2 to the left.
Black and a white connector. Measure on them, one of the connectors is powersupply to the interface +12V and ground, I think the white is signal but I don´t remember.
If it dosen´t work just shift the signalcables, Don´t connect the powersupply in the wrong way!

The powersupply connector is keyed at the short side, the signal is keyed on the longside (cut corners).

Just to clearify: use 2connectors (4cables/connections)