I know this is the B5 thread but i have already posted in classic audi but there was no response. I have a 93 90CS 2.8 12V, and the tach does not work. So i bought an aftermarket tach since i couldnt find a dash anywhere for it. But how would i go about connecting the green wire?

you need to find the tach signal wire on the back of the cluster or you can try finding a rpm signal at the distributor.

Ive looked behind the cluster and nothing is labeled. Do you know where i could find wiring diagrams for it.

You could call up 034 Motorsport and ask them since they pretty much know those cars very well.

Ill call them tomorrow. Thanks