Printable Version of Topic

Click here to view this topic in its original format

914World.com _ 914World Garage _ fuel gauge seems stuck at 1/2 (or should I say 2/4..)

Posted by: potomacmidget Sep 24 2016, 09:29 PM

Hi All,

filled up the other day and it appears that my gas gauge wont' budge past 1/2 full. Any ideas how to trouble shoot? Sender unit, float stuck, etc.? Any advice appreciated.

Car is a 1971 D Jet - all original.

thanks!

Reg

Posted by: euro911 Sep 24 2016, 10:27 PM

The sender is basically a variable resistor that varies the voltage to the meter as the float moves up or down.

Look at the wiring diagram. If you have a VOM (Volt/ohm meter, or multi-tester), pull the connector off and jot down the the resistance readings at the prongs on top of the sender unit. IIRC, it should have less resistance when the float is all the way at the top, allowing full deflection of the meter when the tank is full.

You can short the resistor terminals on the plug to simulate 'full' and 'empty' levels to determine if it's the gauge or the sender gone awry.

Posted by: RickS Sep 24 2016, 10:45 PM

Just had the same issue and was a bad sender.

Posted by: Mblizzard Sep 25 2016, 05:11 PM

Never under estimate the information that removing the sender and checking the operation can provide.

Posted by: Dave_Darling Sep 25 2016, 11:36 PM

The float is probably sticking on the wires in the sender. They can be CAREFULLY cleaned, or replaced.

There is also a failure mode of the gauge itself that causes the needle to stay at one point, but that is less common. Happened to my wife's 911 when we bought it, though.

--DD

Posted by: michael7810 Sep 26 2016, 06:25 PM

Mine did that after sitting for 3 months. It fixed itself after a couple tanks of fuel.