The particulars:
1967 Ford Mustang
390ci

Instrument panel has Tach with clock in upper center gauge location (non-working).
Currently an oil idiot light is located within the Tach (lower left location)

What I wanted to do: remove clock and install a stock oil pressure gauge in its place.

Friend gives me a working Oil Pressure Gauge (OPG) that would be a natural fit in the clock location.

Oil sensor (button like sensor, coarse thread) is located on the top of the oil filter housing.

UNDER-HOOD
1: remove WHITE with RED stripe wire attached to threaded top of button style oil sensor (90degree connector).
2: remove button style oil sensor
3: install Oil Sensor for oil pressure gauge equipped cars (canister type with coarse thread attachment and small threaded post at the top.
4: re-attach WHITE with RED stripe wire to top of small threaded post atop oil sensor.

INSTRUMENT PANEL
After removal of panel to gain access to gauges.

1: detach wiring to clock, Remove clock
2: install OPG in its location (adapted a mounting system that hold gauge in place, made of plastic)
3: cut WHITE with RED wire going to Oil idiot light and attach to right post (as looking down from above) of the OPG
4: Tap off of the constant voltage regulator (using spade connectors) on back of speedo (for power) and attach this wire to left post (as looking down from above) of OPG.

Problem:
Upon moving starter switch to ON or STARTING engine, OPG does not move.
OPG can be grounded separately and the needle will swing fully, so OPG works.

I have been through 3 Oil Sensor switches (canister types). All the same outcome.
I have been told that these sensors should have a ohm resistance of 20-80ohms.
Is this with the engine running and the sensor in its place?

I even tried running a wire directly from the top post of the oil sensor to the right post of the OPG (by-passing any old car wire problems) and still no movement of the OPG.

Is there something special about a 390 oil sensor that I’m missing?

Can some-one direct me on how to connect a OPG what was a Oil idiot light car?


I’m not educated in the electrical ways of things so talk to a simple mind (tab A into slot B type).

Thanks for any help.


Mike