I have a 1991 LX 5.0 and I have been tracking down a problem. I got down to where one of the main harness, the one that operates the fuel pump and other things it is a black type plug. The problem is when it is plug in and i hook up my pos. battery terminal i get a big spark. Could it be a bad groung or bad wires not sure. any info would be very helpful or wiring diagram Thanks.

 

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