To everyone having problems with their TJ (and over) Magna fuel gauges either dropping to empty at a certain point, or moving erratically and then dropping to empty...
As someone else pointed out above, this is a KNOWN FAULT of the TJ series. The fuel sender (the actual float unit in the tank which reads the level of fuel and "sends" the data electronically to your fuel gauge) in the fuel tank is the culprit, and it must be replaced... there's no other way around it. A dealer will charge around $120-150 to do the job, or you can do it yourself if you are a bit handy, BUT it is tricky, and you could end up with petrol all over your car and you.
To fix it (sedan), you must remove the lower rear seat squab. Underneath on the driver's side you will see a round inspection plate. This must be removed. You will then see the fuel line and an electronic connector. The connector must be unclipped and wrapped in plastic to prevent it sparking a fire. Then you need to unhook the fuel line, and this is difficult because of the plastic clamps... patience is required. Once all that is done, unscrew the retaining bolts and lift the sensor unit our carefully. Unhook the electrical contacts and then ease the unit out of its mount. Replace it with the new unit, and then connect the wiring again... then reattach everything mentioned above in reverse order.
Thanks for the useful info, I found that just removing the sender, and cleaning the contacts, plugs and entire sender unit with electrical contact spray fixed my problem. Take the fuel cap off or your tank will be pressurised, or alternately, I undid the retaining bolts first. This releases the pressure and prevents the line spewing fuel in your car. Experience taught me this. I am no mechanic, but hopefully something useful can be taken from this.
That cost estimate looks a bit light - I just priced a new sender from Zupps on the Gold Coast; $159.10 just for the sender.
I'd imagine at least another $100 - $150 for them to do the work.
I might try pulling it out and cleaning it up first.
Thank you all for the easy instructions to replace the fuel sender. I removed the sender from my girlfriend's TJ Magna and found the wiring going to the lowest component (fuel low sensor I think) was rubbed bare against the inside of the tank. Put araldite over the wire and repositioned it so it was not hanging out and the fuel gauge worked. Could not be that dodgy, so got a replacement sensor from the wrecker and found the wire on it was rubbing as well. Am sending the photos of both units to Mitsubishi due to a perceived safety risk. I recommend checking the wires before cleaning the potentiometer.
This might help maybe? There is a setting on the dash for wagon / sedan. The wagon has a larger tank, maybe it is set wrong? To test, disconnect the battery and reconnect, then you turn the key it will have a flashing S (5) or W (UU). Select the one you want by short presses to select, and hold down for a couple of seconds to confirm, then it will give option 3.0 or 3.5 select engine capacity and see if that fixes it??? Just maybe.
Hi, my fuel gauge and odometer on my 2002 Mitsubishi Magna has just stopped working. Can anybody help me?