Making Our Oil Pressure Gauge Read Correctly

[SALEEN961]

As I'm sure you have all noticed our oil pressure gauge is nothing more then an idiot gauge the jumps past half and stays there when there's a minimum oil pressure of 6psi. This really bothers me and I want to make the gauge function like a gauge should and show an actual pressure reading, rather then just indicating the absence or presence of pressure. When I use the gauge test feature on my 99 the oil pressure gauge does a full sweep like the rest of them which makes me think there is hope for this project.

I know I could just install a new gauge but redundant gauges annoy me (monster tachs are the worst), I don't want two gauges I just want one that works and matches the rest of my interior. I was wondering if anyone had replaced the oil pressure switch with a sending unit before and how it turned out.

I'm not sure what kind of sending unit to use or if I'd need a resistor or transistor setup to bring the reading into the correct range on the gauge itself, so any info would be very helpful and save me a lot of money and guess and check work.

 

[Skymarshal]

I wonder if the pressure signal goes through the ECM or cluster circuitry, or if it's just routed directly to the gauge? I'm guessing that the gauge is a stepper motor that is driven by the ECM, so making it fuctional would require not only a variable-value sender, but the gauge motor from the same vehicle.

It would be a big job, but a simple aftermarket oil pressure gauge could be taken apart and the gauge mechanism carefully added behind the cluster with the original needle. I'm sure there would be some clearancing required behind the cluster, and you would have to be careful not to disturb any of the other gauges or backlighting.

I've always been curious what the oil pressure would really look like! Some engines have really low idle pressure, and maybe that's why Ford went with a switch- fewer panicked owners and warranty claims.

 

[SALEEN961]

I looked at a wiring diagram and it shows a single wire from the cluster begin grounded through the switch, since the oil pressure gauge does a full sweep in the gauge test it seems like I'd have to bypass the cluster and wiring up a sending unit directly to the gauge. I'd lose the gauge test functionality on that gauge but I'd have a functional gauge because of it. I might have to leave the current wire from the cluster grounded so I don't get a check engine light, so this too leads me to believe that wiring directly to the gauge will be my best bet.

I just want to see if I can pick up a second cluster to play with so I don't break mine (worse case scenario).