I have a 2002 Blazer. I had a problem with the gas gauge going from indicating full to low fuel and back all the time. I change the fuel pump/sending unit. That problem stopped, but now the gauge is not accurate. Its an 18 gallon take and it reads full when 12 gallons are in. Can the sending unit be calibrated or do I have to drop the tank for a third time to change the sending unit?
