[Avedis53]

Thanks guys. What does that have to do with fuel gauge? They just trying to sell me something?

What your dealership diagnosed makes no sense to me. Both the main and sub fuel level sensor units send their signal directly to the combination meter. I see no connection between the fuel gauge and the A/C Auto Amp.

You said you changed the "float level sensor". Do you mean the main fuel pump and fuel level sensor assembly. The FSM says the entire assembly is to be replaced if the level sensor fails. Do realize there are two fuel level sensors, one for each side of the split gas tank. I don't know which level sensor you changed but your problem may lie with the one you didn't change. Both the main and sub fuel level sensors need to be tested as per the service manual. If the dealership hasn't done this already, they are incompetent. Find another dealership who knows how to troubleshoot a simple gas level sensor.