I have a 67 GTO with a 66 gauge set. The problem is with the oil pressure gauge. I about wet my pants that other day when I looked down and the oil pressure gauge was pegged (80 psi plus). When I started trouble-shooting the situation it appears that I have an electrical problem not a pressure problem. As soon as I switch the key to the ON position (without starting the car) the gauge pegs. I disconnected the gauge from the sending unit by pulling the connector off. Same thing. I put a volt meter on the lead from the gauge and read 0 volts DC no matter whether the switch is ON or OFF. Also when I measure the resistance to ground from the terminal on the sending unit I get a direct short. When I measure resistance to ground from the connector on the end of the wire, I get an open. Any suggestions on what the problem might be before I rip into the dash after that gauge?

I have a 67 GTO with a 66 gauge set. The problem is with the oil pressure gauge. I about wet my pants that other day when I looked down and the oil pressure gauge was pegged (80 psi plus). When I started trouble-shooting the situation it appears that I have an electrical problem not a pressure problem. As soon as I switch the key to the ON position (without starting the car) the gauge pegs. I disconnected the gauge from the sending unit by pulling the connector off. Same thing. I put a volt meter on the lead from the gauge and read 0 volts DC no matter whether the switch is ON or OFF. Also when I measure the resistance to ground from the terminal on the sending unit I get a direct short. When I measure resistance to ground from the connector on the end of the wire, I get an open. Any suggestions on what the problem might be before I rip into the dash after that gauge?

Sounds to me like your dash gauge is bad and needs rebuilt or replaced, EM me I have rebuilding parts for any old 60s Pontiac gauges.
Pete


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Peter Serio
Owner, Precision Pontiac

I would recheck the ground. Also try another sending unit. Putting power to the gauge will peg it. The voltage varies based on the pressure from the sender.

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Gatomon
A car is cheaper than a girlfriend. Better than a wife. If it gives you trouble you can park it and forget about it!