Something with my rpm gauge on my s4 vert is messed up. Every morning when I get up and go to work, my rpm gauge won't turn on. If I turn my car off after it has warmed up, it will turn back on. And sometimes when I am driving it will just fall to zero and won't work unless I restart my car. anyone know whats wrong with it?

 

Is that the only thing that messes up with the dash? If so check the grounds at your trailing coil and check the connectors for corrosion.

 

It's called a tachometer. Your tach is driven off of the trailing coil. First step would be verify that you have spark off of the trailing. Use a spark tester.

 

If you find that the trail plugs are indeed sparking......try rapping on the face of the Combination Meter (that clear plastic cover over the front of the gauges). IF the tach starts working, then suspect a loose or corroded connection on the back of the combination meter. Note: I have to do this every couple of weeks on my 86n/a. It's not worth the effort to fix in my case.

To see if the trails are firing, idle the engine. Then carefully ease one of the plug wires AT the coil assy slowly out of its bore (just a 1/16th inch or less. You should see/hear it sparking. If its sparking, then alls well there. TAkes only five minutes to check out. Go out there and do it NOW! You'll be on your way to success in five minutes. Beats pondering about it overnight.

 

thanks