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ErikJohnson on the .org wrote:Installing an Oil Pressure Gauge

Before doing any work, start with a clean work area, with all the proper tools, and plenty of rags.

For this project, you will need (above and beyond normal hand tools):
-YELLOW Teflon tape
-Oil pressure sensor socket
-3/8" NPT to 1/8" NPT Brass adaptor
-Assorted electrical connections (bullets, ring terminals, horseshoe terminals)
-Terminal crimper
-3/16" Allen key socket for 3/8" ratchet

Ok, lets start by discussing a few options that are available.
1.) Keep stock sending unit, and add the aftermarket sending unit
2.) Remove your stock sending unit, and replace with aftermarket sending unit.

There are a few pros and cons to each for you to consider.

SOHC, you really only have two choices, add the aftermarket unit, or replace the stock-sending unit with the aftermarket unit. I'd recommend that you remove the stock sending unit completely, and replace with the aftermarket sending unit. Here's why: If you want to keep the stock sender and add the aftermarket oil pressure sender, you need to assemble a "T" fitting, and on each end of the "T" is a sending unit, stock and aftermarket. The problem is that there is not enough room in the back of the block to assemble the "T" and then screw it into the block. You have to assemble the "T" piece by piece, on the engine block. Not fun, and there is a large possibility of leakage, since there is not much room to work back there, meaning it is hard to get all the fittings properly tightened.

Removing the stock sending unit will not cause the oil light to come on, ever. *2003+ Years do through a CEL*

Now, installation should be pretty easy. Look at the back of the block, between the 3rd and 4th cylinders, and you'll see a bright green plug. This is your oil pressure sender. Remove the plug (it's got a locking tab in it), and with the oil pressure sender socket, remove the stock sender. You may lose about a cup of oil, depending on how long the car has sat. Be prepared for this, no sense in staining your driveway. Here is where you need to make a decision on what you want to do about the sending units. From this point, either assemble a "T" or use the 3/8" to 1/8" NPT adaptor and install the aftermarket sending unit.

BE SURE TO WRAP EVRYTHING IN YELLOW TEFLON TAPE. WHITE TEFLON TAPE CAN BE BROKEND DOWN BY PETROLIUM PRODUCTS, I.E. OIL.

From here, you"ll need to wire up your gauge. Due to differences in how gauges are wired, I'm not going to go into detail on this. Most aftermarket gauges use a one-wire sensor, so that part is easy. The illumination, ground, and ignition wiring is up to you.

It's a good idea to start you car after installing the aftermarket sending unit, to check for leaks. Take it for a short drive, and look for dampness around the sender. If there is not, you're good. Repair any leaks as necessary.

You cannot use any aftermarket oil pressure gauge with the stock sending unit. What I mean by this is that you cannot skip installing the aftermarket oil pressure sender and just tap into the stock sending units wiring. It does not work, do not attempt. The stock sending unit is an on-off switch, designed to turn on if oil pressure is less than ~9psi.


Cold Idle: 50 psi
Cold 3000 RPM: 80 psi
Warm idle: 25 psi
Warm 3000 rpm: 50 psi

Erik Johnson