the car is an 87 GTA with a digital dash. most things on it seem to work except for the tach and odometer. the odometer just flashes 999999999 like its not set up, but it doesn't really concern me. what does concern me is the tach.
it usually seems to work pretty good but when i am on the highway it gets iffy. after about 30 min on the highway at a steady speed, the tack will start to creep up all the way to the end of redline (6k). when it does start to creep up and i let off the gas, it will fall but it falls the correct increment, not down to the place it should. and if i accelerate it climbs and then stays there.
thank you!