This sounds like you have a short circuit within the fuel gauge circuit itself. When ever you have the positive and the negative shorted within a gauge's circuit, they will always peg out when voltage is applied to the circuit This is because the gauge instead of getting a lower voltage as it normally does, with the sensor acting a sort of variable resistor, is getting full battery voltage from the short circuit, pegging it. In the diagrams down below I have included the wiring diagrams for your vehicle's engine control circuits. The fuel sending unit and the wires you need to check for frayed insulation and causing a short circuit are all highlighted for you. Please go through these and get back to us with what you are able to find out.
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Monday, May 6th, 2019 AT 10:03 PM