Erratic Mondial fuel guage

[saxovts]

Hi I'm new to owning a Ferrari and have a 1986 Mondial, could someone please tell me how to fix a fuel guage that reads erratically when the car is in motion. Thanks.

[drewa]

If the gauge moves an 1/8th of an inch as you go around a curve from side to side that is typical for the type of float gauge Ferrari used in the earlier cars.

Is that what you are seeing or is it worse than that?

If it is worse than that then you have a potential short in the wiring, the gauge, the sender that could be possible culprits. If you could describe in a little more detail would be helpful to point you in the right direction.

[saxovts]

Hi thanks for response. The needle moves alot more than 1/8 of an inch. When reading a 1/4 full will go down enough to trigger warning light and up same distance. Seems like a "dampening" problem with the sender.

[drewa]

I think it is typical. When it is low it will bounce a lot more than when full. If you want to keep the warning light from coming on at 1/4 to 1/8 full tank you will have to remove the float from the gas tank.

Very easy. Either the left or right side of the fuel tank will have a 5 or 6 screw "top" where the sender is located. It is just a float attached to a rheostat. The rheostat has an additional prong that engages the warning light. You can bend it back so that it contacts at a lower fill level.

But I think what you are seeing is typical.

This is in the the Technical archives:
Trouple Shooting and Replacing Fuel Level Sending Unit

[saxovts]

Ok thanks. I guess I'll move onto the next typical Ferrari glitch. Thanks again.