Dancing Fuel Gauge

Posted by Jim L. in OR On 2020/11/15 23:21:08

Hi Everyone, I'm still breath'n.

And having fuel gauge/tank/ and so on.

THE PROBLEM: Drive to filling station and fill the tank - needle rose to F but as fuel was consumed needle would sink to halfway point and go no further until ignition switch is turned off.

STEPS TAKEN: Wiring checked and it's OK. Removed sending unit from tank and it read .000 for Full, .073 for Empty. Checked gauge by grounding out put wire and it rose fitfully to F then moved fitfully up and down. Fitfully, but with a pulse. Cut hole in floor of trunk for access to Sending Unit with tank in place. I am tired of playing with the fuel tank proper. Put everything back together and went and filled the tank up.

RESULTS: Not much. Established that when tank is full needle will, with a steady pulse rise to F then dance up and down All over the place. Incidentally, Temperature Gauge barely registers. Checked Gauge out several years ago by grounding method. It's OK suspect sending unit - just never got around to replacing it.

I suspect the Instrument Voltage Regulater isn't playing the game but would like to hear what more experienced people have to say. Don't want to have to go back behind the Instrument Panel if it's something else.There are things with sharp teeth lurking back there.

Thank you in advance for any help you can give.

Jim L in OR