How to check a fuel level sensor?
 

I am considering buying a 2007 Santa Fe limited (3.3L AWD) with 60500 miles on it. It shows a CEL and code P0464. The fuel gauge drifts from about a half a tank down to almost empty and back over a few minutes. Is there a relatively easy way to check the sensor with (for example) an ohmmeter? Is there anything else I should be aware of?

Thanks,
Terry

Their is a float on the side of the fuel pump case. Unplug the float and measure resistance. New float units are for sale on ebay.

But what should that resistance be? Otherwise how would I know if it is good or not?

Thanks,
terry

A full ground should read full as the resistance moves on the gauge it should vary. Watch as you move the float the resistance moves gradually jumps indicate problems.

Common problem, their are 2 fuel level senders, the one on the drivers side is on the fuel pump assy. and then the stand alone one is on the passenger side.
Both accessed from under the rear seat.

Sub-sender: 9 Ohms (Full) to 110 Ohms (Empty)
Main sender (fuel pump) 4 Ohms (Full) to 69.9 Ohms (Empty)

Enjoy!