Thread: Rpm not working

Car is a 91 sentra ser

rpms jump around freely at all times and doesn't say the actual rpm Im at, I'm stumped don't know where to start diagnosing this issue

after the car is on for a while it will go to about 2000 rpms and stay there, when I rev it it moves very slowly

If anyone could point me in the right direction I'd appreciate it

I have the same problem... Bought my car and it was working fine... about a week later it started shooting all over the place... I tell what RPM i'm at by my speed... haha sucks..

Have you done anything to try and fix it?

out of curiosity do you know what voltage your battery/alternator is putting out

Brand new battery as of yesterday, I will check the alternator tomorrow morning and update this thread, anyone know what sensor is connect to my rpm display?

any suggestions out there? i was thinking the tach but dont wanna buy a whole new one to see it thats the case

my tach once was acting up it wouldnt work unless you tap the gas and rev then it would kick in, it took forever to find the problem but it ended up being a bad connection between the main harness up front in the engine bay its the 2 white plugs by the fire wall i would assume they are on the same side on your car not sure if this is your problem or notu