2005 Chevy Malibu Fuel Sensor gone bad?

ACARDER01

MEMBER
2005 CHEVROLET MALIBU
6 CYL
2WD
AUTOMATIC
83,500 MILES

Last night I stopped at the gas station and filled up my tank. The gas light was already on when I stopped at the gas station. I filled up with about 16 gallons of gas. When I got back in the car and started it, I do just as I always do.I check to make sure the guage went to full and re-set my trip. All of the sudden, the gas guage went all the way back down to empty and the dash information read, Low fuel. I tried 3 different times to turn the car off and then back on and finally it said it was full again, but this time the check engine light came on. I went to Auto Zone right down the street for the free diagnostic test and was told that it was reading "Bad Fuel Sensor Meter". The guage keeps reading sporadic levels and the engine light is still on. Does this sound like the correct problem? Is this something that needs to be fixed right away? And is this going to be a big job to fix? Thank you for your time.

1 Reply

BRIAN 1

MECHANIC
1,030 POSTS

What was the code?Try this:The fuel gauge does not go above 7/8 on the IP gauge after a full customer fill or if the customer claims that they can only get about 12 or 13 gallons into the tank after the low fuel light comes on. The customer might also have a "Check gas cap" message or a P0455 in the PCM.

Recommendation/Instructions:
Use this procedure:

Drain the fuel tank of all fuel.
Drop tank out of vehicle.
With tank sitting on its bottom, check the level sensor resistance - it should read at least 249 ohms.
Lip tank over onto its top-side, check the level sensor resistance - it should read 40 ohms Be sure tank is completely drained before doing this.
These last two steps are referred to as a 'flip-check'.

Remove sender from the tank and do a resistance sweep of the sensor to verify it reads from 249/250 to 40 ohms, from bottom to top, respectively.
If sensor does not verify correct resistance when it is outside of the tank, replace sensor.
If sensor checks out good, put sender into a BRAND NEW TANK and repeat flip-check to verify all is correct inside the tank.
If flip-check does not verify a good system, remove sender and install into a new tank until verified.
If flip-check is good, install tank Assy into vehicle, re-fuel to full and verify IP gauge is correct, and return to customer. Most likley it's the sending unit level sensor.