Abnormal Tach

[g63tawd]

Well just picked up a 85 corolla Gts love the car but it obviously has some minor problems that I am slowly working on. But the one I am stuck on is the tach. It slow starts to climb and then all the sudden it will jump up to the actual rpm then when you shift it will slowly drop down to the rpm you are at. Any ideas would be appretiated. Also the fuel gauge seems to be bad to but I am not sure if it is a bad cluster or wiring or what. Seeing that the car is 22 years old so I just don't want to chase down a common problem that everyone encounters I tried to search but mostley find stuff for installing an aftermarket tach and that is something I don't want to do.

[project trueno]

Have you done a tune-up lately?

The tach could be working flawlessly as is, its possible the erratic needle movement is related to your engine. For example pull the plugs, what condition are they in? Start checking the ignition system first, and see if everything is still within spec.

[g63tawd]

I was actually going to go over the car in full this weekend. I was just looking for ideas of where to look. Thanks