Quick Question. If my gas gauge goes, lets say afterfillup, then goes to E with the gas light on, then spikes back up, then goes back down...is that probably a bad gas cap?

 

prolly a bad sensor in the tank, i dont think the gas cap has to do with anything

 

Nothing to do with the gas cap. Its the sensor in the tank. I hate to keep referring to my 1995 Dakota like in other threads, but again this same thing happened to it. Took it to a dealership, they quoted me somewhere around $300 just for the sensor. Went to a reputable mechanic, he did everything, parts and labor, for around $250.

Correction: Its not called a sensor, its a fuel pump sending unit.