mezzyshreder

Hey guys, I have a 94 Z28. Gas gauge was always off a bit like a lot of 4th gen F bodies, however ever since I filled the tank recently, the needle does not move and is stuck between 1/2 and 3/4, weather the ignition is on or off. When I would go into a turn prior to this, the needle would sway drastically. Now it doesn't move. Is this most likely a broken wire in the sending unit? Is their another part that could be bad? Any help is greatly appreciated.

Summitracing

It sounds like there is a break in the wire, corrosion in a connector, or a faulty sending unit. You will want to make sure the sending unit is working properly by using an ohm meter to check resistance as close to the sender as possible. The connector is above the driver’s axle that will have 3 wires goes to the fuel pump. The gray wire closest to the driver side is the 12v fuel pump, middle wire is the sender and passenger side black wire is the ground for the pump. You will want to check resistance on the tanks side of the harness and ground. Compare it to the figures below for proper operation.

Your reading should be similar to the following
• 90 ohms = full
• 60 ohms = 3/4
• 45 ohms = 1/2
• 26 ohms = 1/4
• 1 ohm = empty

If this reading is correct, with the connector still unplugged check the chassis side of the harness. The middle wire should have no continuity with ground. If you are reading resistance you will need to trace the wire on the car to look for the break or worn insulation.