I have a '91 rs 305 5sp and i loved that car deeply!! my prob is my tach! when i crank the motor it seems to work then when the car is running, the tach maxs out!! Anyone have this prob and what is a good fix, the dealer said i'd have to send the dash in for a new tach and i dont think thats the prob! Any help greatly appreciated and also motor surges when heater or defrost is put on, if i turn them off the motor idles fine at a stoplight.