I've got the 5 bar Volvo oil pressure gauge that was working until this weekend. I put in a small clock that I got out of the junkyard, and moved the five bar gauge from the top hole where I wanted the clock, down to the one below it. It was a simple thing that only required me to disconnect the wires and put them back together. I've got the small clock in successfully, but when I put the oil pressure gauge back in now it doesn't work. When I turn the key on, the needle pegs all the way to the right before I even start the car. And then it stays there, even when I shut the engine off and take the key out. If I tap on the glass then the needle falls back down. Tapping on the gauge doesn't do anything while the car is running, it's always pegged.

I am 99% sure that I wired it exactly like it was. Any ideas?

The oil pressure gauge will peg at the top if it does not get a ground signal from the sender. ie no resistance = top of gauge, direct ground on "G" terminal = a 0 bar reading.


My guess is either a wire is loose or the sender chose that moment in time to die, these senders do die at their age but having one die just then is unlikely, check for a loose wire. + goes to the fuse box, the upside down T is ground and the G terminal is wired to the G terminal on the sender.
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Dave Shannon
Spring Valley, California
'84-245T 190K+
'88-240 190K+
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Jeep Wrangler Sahara 10K
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