Hello all, I'm doing some work on my church's bus, and could use some help. It's a 98 Ford/Bluebird. 5.9 Cummins, Auto. We've been having issues with the fuel gauge. It'll hang at the far right of range (well beyond full) for a long time, then suddenly drop down to around 1/4. "Sticking" the tank yields a measurement of around 1/2-3/4. So, it's nowhere near accurate. We had it in the repair shop for other issues, and they believe it's the gauge itself, and want $200 to replace it. That sounds way too high to me. I pulled it out and got the part #, VE9HF-9305-AA, F-Series H/T Fuel. Electrical stuff is not my strong suite. Is there an easy way to test the gauge? Where would I find a replacement? (used is fine) All the parts stores I go to online don't recognize the part #, or even have a category for heavy trucks. There appears to be plenty of room in the dash cluster to make up a bracket and just mount an aftermarket gauge in it's place, as a last resort, but I'd rather just plug in another Ford unit, and go. Again, I'm no expert, but it's seems to me the sender would be the more likely culprit.

 

The fuel gauge is really nothing but an ohmmeter. The float arm on the sending unit in the tank is attached to a rheostat (variable resistor) and the gauge measures the resistance as the float moves up and down. I know that in 1989 the rheostat was a printed circuit board with tiny solder tracks that wore off as the contact point on the float arm rubbed across them. My guess is that your sending unit needs to be replaced.