I have a 1993 XKS 4.0 with a 6 wire rectangle plug (not a round plug) and I need to know whick color wires do I use to check the Volts for the TPS. There should be 2 colored wires that I will use the Volm meter across to set the TPS at 5 to 6 volts. at idle. I just don't know which color wires I should be checking.