My tach. is very unstable when idle and driving but everything else is okay. Can anyone give me pointers to fix this problem?? Is this a common problem? Thanks.

 

is just your tach and not your car? if the actual rpm of the motor is causing the problem then there are way to many things to list that could be wrong. other wise just check for loose connections behind the gauges or just replace it they arent that expensive at a junk yard.

 

the car runs fine, so i think it's just the tach problem.