I'm driving down the road and both the speedometer and tach droop to 0 and fluctuate while the car runs fine. What would cause this? Also I did have problems with it starting once. Please help I got to many ideas to start with and maybe someone here can shed some light on the problem.

 

cluster connector is where i would start. also start checking grounds.

 

What about the vehicle speed sensor? I know that can affect the speedometer but what about the tach?

 

im not sure. i dont see why it would affect the tach at all. the tach signal is pulled from the dizzy. neither should have anything to do with the other. thats why first guess was cluster harness connector or wiring.

 

thats exactly what I was thinking except for if it was the cluster connector wouldn't it affect all the other gauges too or is it possible maybe the connections at the dizzy?

 

i dont know wiring isnt my thing, but i know the dizzy wiring has nothing to do with the speedo, and the vss wiring has nothing to do with the tach.

so ????

 

im actually having the same problem with my car but my dizzy is messed up so my car is constantly turning on and off while i am driving so that was my problem

 

i think it could be your alternator going bad. my car did the same thing your saying your car is doing right before i changed my alternator cause my car got to the point where it wouldn't turn on at all unless i charged the battery all the way and then it would just die five minutes later. so im pretty sure it's most likely your alternator going bad but see what other people say first.