Does the tachometer receive its signal from the ECU or from the ignitors? The rpms occasionally increase on the tach, even though the actual rpms are constant. It goes from like 2500 rpm to 6000 rpm for a few seconds, then goes back to 2500. So far, engine performance is not affected- like injector duty cycle at specific rpm- so it may be just the tach that is messed up. Any suggestions appreciated, other than spending several hours trying to trace the wiring diagram in the FSM.
Ron A.

 

Try reading over this page.

Gauge Replacement

 

Thanks- I forgot about the bad solder problems that are common on the interior electrical components. My wife's 2nd gen had a problem in the ECU that made her horn and some of the warning lights inoperable. Re-soldering the circuit board connections fixed the problem.
Ron A.

 

No prob

 

Anybody? What is the range of the tachometer input signal?

Thanks

Mike