i wired the yellow wire off the trailing coils to my Yellow/blue wire of my tach, and it doesn't work. I put the monster autometer tach on to that yellow wire also, and doesn't work. Looking at my laptop i know the ECU see the RPM, how come i don't get any readings on my stock and aftermarket tachs?

 

I had the same problem with my stock tach and it turned out to be faulty ground somewhere. I just ran a wire from the coil's bracket to a bolt nearby on the firewall and it cured the problem.

So, I can't offer a specific cause, but you might check and fortify your grounds through that system.

 

thanks alot, i'm going check it out tomarrow.

what other grounds should i add? is their a main wire source for the grounds? i notice once i took out microtech i took out alot of grounds that the stock ecu needed, i was thinking adding more grounds but to what?

 

Sorry, mine's a stock S5, so anything past what I've mentioned is beyond my scope of experience. There is a lot of conversation on the Forum about grounding. A search might reveal the answers to your questions about it.

 

I just wired my tach a couple days ago what kind of tach do you have is it by autometer?

 

yeah my tach is an autometer one, but the thing is the autometer one doesn't work nor does my stocker, so i think it's what attomica mention, i'll see if a good grounding will do it.

 

Yeah the wire thats blue and yellow in my car it green and yellow toward the left front of my car is that where yours is if so try checking your fuses and see if its burnt