I have an 04 malibu classic, just bought, runs great, they replaced the engine,
But he said the fuel gauge when filling will only go to half and then stop , but ya can put a full tank of fuel in. But the gauge wont start dropping till of course it goes less then half. Its ok, since i want to know when it gets close to empty, but would like to know whats wrong, i said probebly the sending unit, but he said he took it in and they said something about the ignition was the issue why it does that. Never heared of that.

has anyone heared of that issue, or would you think it would be the sending unit bad?

 

04 was one of the years that GM had problems with their stepper motors in the gauges. It is possible that is what is causing your problem. However it does sound like the sending unit.

 

maybe play with gauge a bit lightly maybe or just replace the sender...

 

The arm that has the float on it may be binding and not go up all the way or the resistor is bad. You will only find out by taking it out.

 

I'm guessing its the original. Yea didn't want to drop the tank. But should do it anyways, has a filler issue also, the gas pump keeps clicking off so... maybe filler tube to tank is messed up, or the vent tube, do it all at once. Are these tanks fairly easy to drop? as in the fuel lines removed etc? anything i should expect under there lol I need to replace the rear trailing arm also, so yea do all at once.