I was curiuos what the symptoms of a bad sending unit would be ? would it cause the pump not to work or go bad? I installed a new pump a year ago and everything worked fine guages fuel pressure ran nice. I have been restoring the car so it d has not left my garage in a couple years. I took the intake and phenum off to powder coat. When I put it back together hit the key heard the fuel pump relay kick in . but no fuel prime or pump running noise like before. and the fuel guage goes way beyond full when the key is on, when off it will drop a little below full. I am baffled at this. everything except the sending unit is new on this car. what have I possibly done?

 

Going up past full means there is an open between the gauge and the sender, or the sender itself is bad. Start by grounding the sender wire at the tank. If it stays at E, then it's the sender. I don't see how this could be related to what you did to the engine unless you left off a ground wire somewhere.

 

Sounds like the wiring harness that goes to the tank, isn't plugged in.

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