I have a 96 GMC 3500HD dump truck with a 7.4L gas engine
that has gas guage problems. I understand the principals and components of the dual system tanks. When the truck is first started the gas gauge needle will move to about 3/4 empty, and wiggle for about 10 seconds. After that the needle falls below empty and does not come back on until the engine is shut off, then the cycle starts again. I've checked all the grounds and connections and all seems tight and secure. Where should I look now to get my fuel gauge working correctly again.
JA: Has the vehicle turned into a gas hog? And how does it start -- same as usual?
Customer: starts normally, and doesn't seem to be a gas hog. although its hard to tell
JA: What is the model of your '1500 GMC?
Customer: 1996 3500HD 7.4L Gas
JA: Are you hoping to fix this yourself? What have you tried so far?
Customer: yes, checked fuses, grounds and connections
JA: Anything else you think the mechanic should know?
Customer: not that I'm aware of