Help me... my rpm gauge don't work! I have a 79 rx7 with a 85 gsl motor in it. I have re-wired the distributor for full time ignition ! When I start my car it turns on! But the rpm gauge don't work! I put key to on but not turned over and rpm goes to 6000 rpms when I turn over the key and it right before it turns on the rpm gauge is at 3000 then when cars on the rpm is at 0.... What could this be?

 

Check if your trailing (top) plugs are getting spark. The signal for the tach comes from that ignitor.