Fuel level sender replacement

[alexmak]

Of course right at the moment when you feel like everything is perfect, nothing is leaking and the car runs great, something starts to misbehave.

two weeks ago my fuel gauge was working perfectly. A week later on my way to a cars and coffee meeting I noticed that the gauge started going from full to empty about every 10 seconds. I added some fuel, it went to full, and while I was driving for an hour and a half, it was showing slowly reducing amount of fuel properly. But then once I parked the car in garage, the gauge went to empty again, and it stays there, although I know there's 3/4 fuel in the tank. When I turn on the car, the gauge needle reacts by lifting for probably several millimeters, and then goes back to empty, and stays there. so to my unexperienced eye it looks like a possible issue with a sender unit.

so I'm going to drop the tank and see what's going on, and potentially replace it. what's the recommended part # to replace the one that came with FFR kit?

[Blitzboy54]

You should not need to drop the tank to replace the sending unit. There is maintenance panel in the trunk. This is honestly a fairly easy thing to do. Any Fox body era unit will do.



https://lmr.com/item/LRS-9275BR/1987-93-Mustang-50L-Fuel-Level-Sending-Unit?utm_source=google-shopping&utm_medium=comparison-shopping&utm_campaign=google-shopping-v2&year=1993&adpos=&scid=scplpLRS-9275BR%231993&sc_intid=LRS-9275BR%231993&gclid=Cj0KCQjwmuiTBhDoARIsAPiv6L99r2Cft68COCjKzM0f PA1sUwLBhH1B6svtVONW8_IHIkKt4nNxpyAaAp2jEALw_wcB


https://thefactoryfiveforum.com/attachment.php?attachmentid=149190&d=1623099830

[Jeff Kleiner]

The fuel sender is from a 1987-1993 Mustang but my experience with Speedhut gauges leads me to suspect that it may well be the gauge rather than the sender. Read the ohms across the sender; as you seeep it through the range it should smoothly go from approximately 18 ohms empty to 158 full.

Jeff

[alexmak]

The fuel sender is from a 1987-1993 Mustang but my experience with Speedhut gauges leads me to suspect that it may well be the gauge rather than the sender. Read the ohms across the sender; as you seeep it through the range it should smoothly go from approximately 18 ohms empty to 158 full.

Jeff

thank you, Jeff. Yes, I'll do the readings on the sender and see what happens

[rich grsc]

Agree with Jeff, not the sender

[alexmak]

You should not need to drop the tank to replace the sending unit. There is maintenance panel in the trunk. This is honestly a fairly easy thing to do. Any Fox body era unit will do.



https://lmr.com/item/LRS-9275BR/1987-93-Mustang-50L-Fuel-Level-Sending-Unit?utm_source=google-shopping&utm_medium=comparison-shopping&utm_campaign=google-shopping-v2&year=1993&adpos=&scid=scplpLRS-9275BR%231993&sc_intid=LRS-9275BR%231993&gclid=Cj0KCQjwmuiTBhDoARIsAPiv6L99r2Cft68COCjKzM0f PA1sUwLBhH1B6svtVONW8_IHIkKt4nNxpyAaAp2jEALw_wcB


https://thefactoryfiveforum.com/attachment.php?attachmentid=149190&d=1623099830

Not all of us have this maintenance panel

[jab351w]

so I'm going to drop the tank and see what's going on, and potentially replace it. what's the recommended part # to replace the one that came with FFR kit?

If it does wind up being a bad sender I have a used working one you can have for shipping cost. I had similar issues with the gauge jumping around and replaced the sender but it turned out to be a wiring issue.

[BradCraig]

My gauge is doing the same thing, curious to see how this works out.

[egchewy79]

if you're dropping the fuel tank, check the wiring connector first. I found out that my fuel sender harness wasn't fully clipped in because the contacts inside were a bit off and needed to be bent to fit. I wouldn't have recognized it until I noticed that my fuel pump harness snapped down much further than the sender harness. This might explain the intermittent signal you were getting.
also while the tank is dropped, consider making an access hole through the trunk floor.