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Ignition Wire - Gauge Install


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2:53 PM
Apr 16, 2020
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Hey guys - mounting my oil pressure gauge on my cowl. Have everything plumbed just need to wire.

A) Does anyone know what wire would be considered to be ignition inside the firewall? I know I can go into the orange wire inside the car, but would like to connect to one of these inside the engine compartment if possible.

B) If there is a wire in the pic that would work, suffice to T into that wire for power for this gauge?

1967 Coronet R/T and AutoMeter mechanical Oil Pressure Gauge. And yes I have braided steel line - and connected a power wire to battery to test and it works.

Thanks in advance!

There are several vacant locations on the top connector. Run your wire through one of those to connect under the dash.
This gauge does not need power to operate. [[[[[[[[AutoMeter mechanical Oil Pressure Gauge ]]]]]]]]
Orange wire under the dash would be a light circuit, I believe.
There are several vacant locations on the top connector. Run your wire through one of those to connect under the dash.
Thanks Jerry - just as easy as connecting into a wire at that spot I presume.

When I get to the bulk head inside the car - best to splice into the orange - or is it Red? Ignition wire for the gauge power or add to the backside here? No open spots.

Wiring is not my forte - ha. Thanks!

You said you had the gauge plumbed, and I assumed mechanical gauge with two wires. One is ground and the other for the light. If the gauge is electrical, there should be three wires, switched 12V, ground, and 12V light circuit that works with the headlight switch (orange wires under the dash). If you know how to use a test light, it's easy enough to find a switched 12V wire.
Indeed mechanical. So run red through firewall to orange (splice in?) and black to any ground and good to go? Thanks!

Fix the Black wire looks about to short out in post #5.
There should/may be a splitter with bullet connectors for various dash lights.

Trace some orange wires and see.

May be near the ashtray to connect lights (whether they're there or not) in the console (whether it's there or not).