Questions and Answers
Ford E150 Fuel Gauge Is Wrong
Q. Hi, I have a 1989 Ford E150 van and the fuel gauge is dead, shows empty when van FULL. What should I check?
Thanks,
JackA. There was a TSB out on damaged fuel tank sending unit connectors, so that would be the first thing to check. If the connector is damaged, you can get a replacement from Ford, P/N E9FZ-9A400-A Wire Harness - Fuel Pump. Also ask them for a copy of the TSB, Article No. 89-14-6, so you have the instructions for installing it.
If the connector is good, ground the yellow/white wire. With the key on, the fuel gauge should go to FULL. If it does, the dash gauge is good and the in-tank sending unit is bad. If it doesn't, then the dash gauge is bad. 90% of the time it's a bad sending unit, but the test is easy enough to do to confirm it.
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