Fuel Gauge reads empty all the time

You will need to test a number of things, the fuel gauge is part of a rather simple circuit.

Battery -> gauge -> tank sensor -> chassis ground to battery

If the circuit is broken at any of the steps, your gauge will read "empty". If the tank sensor is bad, it could read empty, or if the float in the tank has sunk, it will read empty.

I start at the gauge with a "test light" that glows when it sees battery voltage. Get a light at the connection to the gauge? Good. find the sensor connection, usually on top of the tank, accessible in the trunk. Probe with test light. Light on? Good. Connect wire to ground, gauge should read "full". If all that is as I said, then the tank sensor is bad. If you don't read battery at any step, you know where the problem is.

The fuel gauge sender is mounted internally in the fuel tank. There is a three pin connector that will have a Yellow/White wire in it (the middle wire) under the center console. This is the sender wire. Connect an ohm meter between this wire and the black wire and check for the following readings:
If fuel tank is full, the reading should be 7-14 ohms. An empty tank should have a 74-95 ohm resistance. A half full tank will be approximately 30-38 ohms.
If you ground this wire that comes from the harness, the fuel gauge should read full. If not, then fault may be in wiring or the fuel gauge itself.
Remove the front fairing to gain access to the gauge. You should have 12 volts across the orange/white and black wires. If not, check accessory fuse. If 12 volts present ground the yellow/white wire at the gauge. Gauge should read full scale. If not, gauge faulty. If gauge reads full scale, check wiring from gauge to three pin plug under tank console.

Is this a flex fuel vehicle. If so, call the dealership and ask the parts dept. if there is a gauge module (perhaps behind the instrument cluster). This may be the culprit and needs to be replaced.

when the tank is full the resistance is low so the power through the gage make is read full
as the tank empties , the resistance increases so the less current means the gauge reads less until empty there is little or no power , the gauge reads empty
simple check , turn the ignition off, no power , no gauge reading

Contact me directly and I'll send you some information on the principle of operation and troubleshooting the gauge. It's out of an older manual but the principle is the same and I think the readings are the same. The float is on the sending unit and usually if the float goes bad, it sinks and the gauge should read empty all the time. But, since the original did the same thing, it shouldn't be that the arm got bent either. [email protected] Make sure you remind me of what you need.

Steve

2005 PT cruiser, i replaced the cam sensor with a aft market sensor my fuel gauge started reading wrong, and it didn't fix my problem so i replaced the cam sensor with a factory sensor it fix my running problem but the fuel gauge still reads wrong, with a full tank of gas the gauge reads 3/4 tank,

chevy and gmc trucks have an on going problem with this,turn the key on,and get a rubber mallot or a hammer and hit the bottom of the fuel tank a couple of times,this will unstick something in the fuel pump/sending unit.

The gauge circuit is shunted on most cars, this is wierd, but needed to stabilize the readings... Your description sounds like normal function. Drivers would complain if the qauge were to be instant, going around corners, starting, stopping, all move fuel, and the gauge would indicate this, cauing driver alarm...Been this way for ever, although yours sounds like it is on the far side of the scale...if it reads correctly after a while, you could replace everything and you would have the same performance.

sounds like a fuel sending unit problem or an issue with the sending unit's float. May need replacing. HD- hundred dollar

no need to remove tank, Remove terminal pins from connector under left side of tank then pull gauge and wires out. Install new gauge, replace terminal pins in their propper place in the connector,plug it in and varify the repair.