An oil pressure gauge can be a crucial device for monitoring the health of your engine. The gauge is a simple device that reads the pressure being produced by the engine's oil supply via a thin tube that the oil runs through. An oil pressure gauge can be a good indicator of your engine's health, alerting you if there are any problems with the engine's oil supply.
Slide the end of the clear oil line into the fitting on the back of the oil pressure gauge, tightening the fitting onto the line with an open-ended wrench. Apply Teflon tape to any metal parts that thread together.
Determine where you are going to mount the gauge in the A-pillar. You can mount it in a variety of ways. You can use a gauge pod that mounts somewhere like the A-pillar or dash, or you can custom mount it anywhere you choose. Just make sure you can see it from the driver's seat.
Ground the black wire for the gauge lights to a suitable ground. Fasten a round eyelet to the end of the ground wire and bolt it to a metal surface that does not have any paint on it. Splice the power wire for the gauge light into the existing gauge light wiring harness. You can use an inline splicer or simply cut into the wires and tape the gauge's power wire to a wire that runs to the existing gauges.
Run the oil line through the firewall and into the engine bay after you have mounted the gauge. Locate an existing hole that wires go through and use that for the oil line. If you cannot locate a hole, drill a small hole. Insert a rubber grommet in the hole to protect the oil line.
Locate a suitable threaded oil fitting in the engine's block. If your car uses a factory oil pressure gauge, use that fitting to install the new oil line. If your car has an oil pressure warning light, this will also be installed in the block, but it will likely be only a wire that runs to a sensor.
Install the threaded fitting that came with the oil pressure gauge on the other end of the oil line. Wind Teflon tape around the threads on the fitting to prevent leaks. Thread the fitting into the block. The gauge kit will likely come with several different fittings that have different threads to fit a variety of makes. Start the engine to ensure the oil gauge is correctly reading the engine's oil pressure.