Fuel gauge goes down at stop but rises again when accelerating.

IF YOU FILLED THE TANK WHILE THE ENGINE WAS RUNNING THE GAUGE WILL NOT RESET FOR A WHILE BUT WHEN YOU TURN OFF THE ENGINE & RESTART IT SHOULD GO UP TO FULL AGAIN IF NOT YOUR FLOAT IN THE TANK MAY BE LETTING IN GAS WEIGHING IT DOWN SO IT WON'T RISE UP /// OR THE FUEL SENDER CONTACTS ARE VERY DIRTY OR A WIRE HAS COME OFF

Hi there must be a problem with the fuel pump or fuel filter or there is some vacume leak maby . thnx

run the fault codes first to check for faulty sensors
what you describe indicates a problem in the exhaust in that when the exhaust gas volume reaches a certain level the sensors are reporting it and the ECM is not able to fix it
have an accredited exhaust shop check the cat converter
for failure and partially blocking the exhaust at speed
if it was a fuel pump you would run into problems long before the speed at which it occurs
AT best it could be an EVAP problem with the vent not working properly but I think that it is exhaust related

It sounds like there is a leak of some sort. (hose, freeze plug, water pump, blown head gasket, etc.) The coolant level is probably low. You need to check it ASAP! Check the coolant level and if it is low you need to find out why and get it repaired...You DON'T want to overheat that engine! Especially if you have the 3.0L V-6. It only has to overheat once to do some serious engine damage.

sounds like a fuel level sender problem

very well sounds like the sending unit in the tank. Try running some octane booster and fuel injection cleaner in tank of the truck to loosen any deposits on the float.

Did the mechanic use an OEM replacement unit or an after-market unit? I think the original unit has a damping circuit to prevent immediate response when accelerating/stopping/cornering; the needle reacts slowly to changes in fuel level. If the new unit shows an immediate transient response, but settles back down to the actual fuel level, I'd just live with it.

Mine too! I have a 2007 Chevy Malibu also and I knoticed it does that or bounces up and down once my tank gets to half full. Have you found a solution? Sometimes my check engine light comes on and sometimes it doesn't.

maybe a bad wire to sending unit, or a bad sending unit, the engine light may be related to the gauge problem, go to autozone have them scan the computer if the code has to do with the fuel level sender, then check the wiring if its good then replace the fuelpump asm, the asembly will come complete with a sender for gauge,when replacing make sure baffle is not floating around in tank.

You will need to replace the fuel level sensor which is in the fuel tank.They have a lot of problems because the metal fingers on the sensor wear off and gives you the incorrect readings.This will also cause the check engine light to come on.You will probably have a level sensor code.This will be a lot easier if the fuel level is down to about a quarter tank or less.Also you should be able to get just the level sensor and not have to get the complete fuel pump module.Good luck.