Whacky Tach

[SHIP4BRAINS]

1990 F350 7.3 IDI

My tach is going bonkers. Above 1000 rpm it works fine. When at idle, it will from time to time bottom out to ZERO....a light tap on the accelerator will bring it back up to a high idle....remove my foot and the needle may or may not drop back to zero...

???

 

[hesutton]

Sounds like the sender is on it's way out. Ford only part if I remember correctly. About $50 at the dealer.

Heath

 

[tractorman86]

mine's doing the same, does it get worse when you have your headlights on?

 

[NJGearhead666]

yea mine does the same thing