Nuttynotty

Hi Guys,

Hope someone can shed some light on a problem I have with a 89 Audi CGT, nothing major.
I have checked my manual and can not find where the dash picks up the RPM signal.
My RPM gauge has never worked and I’m thinking I would like to get the stock one running again, be a nice tough.

So basically, where does the RPM gauges pick up the plus signal for the engine, or is it vir the onboard Computer. Any direction or pointers at this point would be great.

Also I do not know if the RMP gauges evens works as in mechanical / electrical, so if there are any pointes on how to test even better


Cheers

Rogviler

I know there's a way to test the tachometer, but you need a special piece of equipment that generates a pulsing signal.

The tach on these cars gets its signal from the ignition coil. I forget what color the wire is, but it's one of the small ones plugged into the top of the coil.

So basically, if the car runs you know the problem is between that connection and the tachometer itself.

Have you taken a look at the back of the instrument cluster? It's a notorious place for corrosion because water can get in through any number of holes under the dash (such as the speedometer cable hole). Sometimes just unplugging the connector a few times will take care of it. There could also be a broken connection on the cluster itself.

But I've also had a tachometer go bad. I ruled out all the other stuff and decided that had to be it, so I swapped the cluster out and the new one worked fine.

-Rog

Nuttynotty

Hi Rog,


I'v had the das apart, as the clock did not work, that turned out to be a cap, once replaced the clock works great. Yes I see the dash is a little crappy from water, but all of the connections are good, I did not see a wire for the tack, and being the PO was a "Hack" I bet the wires were cut or removed ?


I'll start looking around the coil, thank you for information, this is a huge help :-)


Cheers