View Full Version : Tachometer is acting up!!!!!??????

08-27-2002, 02:03 AM
hey there everyone, i got another question for you guys. I will be driving in my 91 sc and the tach will just drop to 0 RPM's and the engine wont turn off, then my check engine light will appear. Soon after that the tach goes back to normal and shows the RPMS and the check engine light comes off.....I have no idea and I think that i should do a computer test with my car but i am not sure how to do that either. Does it have to do with using the key in the ignition???? Well if anyone out there knows then please let me know...thanks

08-27-2002, 02:33 AM
I had the exact same problem with my 91 auto, I'd be drivin along and all of a sudden the rpm gauge would just die, and the check engine light would come on. Within a few minutes, it would go right back to normal, C/E light would go off, and rpm gauge would come back to life.

1- run a computer test and see if it pops any codes (you can buy a code finder at a local parts store i think)

2-check the wiring harness that goes to the dash cluster and make sure there is no cut or bare wires.

3-the gauge itself might be bad, if thats the case a junkyard unit should fix that providing you can find an sc in a junkyard.

I'm no master mechanic, but these are the things I'd check before bringing it somewhere and paying somone to do it.

08-27-2002, 10:43 AM
Cam Sensor(CID sensor), Controls siginal to tach. On my sho it was full of rust easy to replace and not that expensive $35-$45?. Not sure where it is on my tbird though. Does the car buck at all?