57droptop

My '57 has a fuel gauge that was replaced at one time. It works perfectly - in reverse! Full=empty, empty=Full, with accurate (backwards) readings in between.

I read something on a blog about oil pressure gauges being substituted for fuel gauges and causing this problem...? Have tested the sending unit but it seems to be OK.

Any thoughts? Thanks -

svnt442

This is due to the gauge not being correct for the fuel sender.

oldcutlass

If you remove the wire from the sender with the key on what does the gauge read? Should read past full.

If you ground the wire with the key on what does the gauge read? Should read empty.

Human

Reversed polarity? Maybe somebody wired it in backward. Stranger things have happened.

57droptop

Randy,

Thanks, sorry for my extremely tardy response. I do know that the gauge was replaced at one time; apparently they fudged it with who-knows-what; lends support to the oil pressure gauge theory...I have looked everywhere but haven't been Abe to find a replacement gauge.

57droptop

Only has one wire to the gauge, though the gauge itself has two poles...

svnt442

When I say not correct I mean the OHM value doesn't match what the sender is at full and empty. If you go to the autometer site and look at fuel gauges you'll see at least 3 different ranges for fuel gauges. Some are high ohm when full, some are low ohm when full. That is what will cause the gauge to read backwards.