Ok here goes, maybe socal will chime it and give me the facts. I put my hhr in the shop for a leak on the passenger side. Well they fixed that but disconnected the battery to replace the carpet and the gasket around the cabin air filter box. Ever since then my gas guage will indicate like 1/8 of a tank and for no reason I know of it will go back to Full. It is not moving or incline related. I asked the service manager at my dealer and they said that I should not overfill the gas tank, and that was what was causing the problem, something about gas overflowing/sloshing into a canister and causing the problem. They said that I should quit putting gas in as soon as the pump kicked out the first time. Well the problem I have with this is that for 7 months I have been doing the same fill up routine and have had no problems with the gas guage or my DIC mpg etc, now right after they work on my car the darn thing isn't working right. Ieg. I have appox 118 miles and today the guage was indicating only 1/8 of a tank used but the DIC said 26.7 mpg. Any help would be appreciated here but from my experience, not a mechanic, there seems to be some major BS flowing ....

 

hey jwolfe, just wanted to say Hi !! I'm originally from Humphreys Co. MS...

 

there is a charcoal canister that can get damaged by overfilling that why they say don't overfill but i've never heard of the gas guage getting damaged

 

sounds like a fuel sending unit to me

 

Same here
fuel sending unit

 

Thanks guys will take it back and make them fix it but why would it happen right after they worked on it?

 

My ... double check your fuses (under the hood and in the cabin) *before* the dealer- might prevent another unnecessary trip!?!?

 

Sounds like a dealer that doesn't want to work on it. I'd take it back and start up the line until I got to the GM Rep.