79 MC fuel tank problem?

[willchillz1]

Hi everybody im new to the sight this is my first question....1st off my gas guage doesnt work on my 79 MC currently, but even when I know there isnt much gas in the tank, the gas wants to overflow when I want to put gas in it almost right away sometimes. Does anybody know why that could be?

 

[84GP455]

It sounds like you may have a venting problem. Was a new gas tank or sending unit ever installed on this car before? the vent tube could be pinched or blocked which could cause the tank to burp up the gas because it can't vent the fumes fast enough. another thing with your gas gauge not working could be a bad sending unit.