3. I turned the key back to the on position one more time, so the TPS could be set. The TPS on the Holley unit is adjustable, thanks to the slotted holes in the side, which is not always an option with the factory pieces. The sensor needed to be set to 0.65 volts. Using a paper clip to make some probes, I tapped into the black and the blue wires. Now a multimeter will tell me what the TPS is reading.