"Normal" Oil pressure switch funky?

5.0aintslow

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May 22, 2019
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Hey all

Pretty general noobie question, but I've heard a bunch how the oil pressure "sending unit" in Foxs 302's is more a switch than a variable sensor? Meaning its either on or off, and the gauge is in fact more of a dummy gauge than anything? Reason I ask is cuz sometimes my oil pressure reads out around the halfway mark or "M" in "Normal", and sometimes its hanging right on "L" (this is what concerns me lol).

Ive cleaned the connection nipple to the switch, and ruled out that all grounding wires are fine. The needle somedays will move with RPM changes, but days like today, it kinda just stays just above "L" and doesn't move with RPM. No funky noises or anything, it runs like a top! New switch is in the mail tomorrow, will put it in and cross my fingers.

Oil is Castrol GTX 10-30, engine just hit 200k kms, never drips or burns any oil, no blow by either.

Thanks!
 
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Mustang5L5

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Mod Dude
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Mine definitely moves, although the motor needs to be very warmed up for it to do so.

Mine usually hangs up at the top range of normal, but once the oil is nice and hot will drop down to around the L.

I've had a mechanical oil pressure guage installed and have seen 60 psi of pressure when motor is revving and no lower than 30psi at idle. I don't worry about it
 

08GT500

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Jul 12, 2018
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Hi, Think that would concern many!
As it warms up, viscosity changes, pressure drops, especially at idle. Sounds like a Gauge issue, but personally- I’d not take the chance.
My suggestion is parts store & buy a good Ie; Auto-meter, etc. Mechanical Oil Pressure Gauge & thread it into an Oil galley, you can use the OE spot, or jump to another. Stick the gauge into a pillar pod, neat & within eyesight, then you’ll confidently know where you stand when you’re running.
The factory Oil Pressure Gauge is driven off a variable Pressure differential platform, but gives no specific measurement & is less than acceptable in quality, to boot... OK- Junk!
Every performance Car I’ve had/have gets a Mechanical Oil Pressure Gauge installed. Simple & effective, when correctly setup, there is nothing more reliable...
Good luck
 

5.0aintslow

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May 22, 2019
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Thanks for the replies! Yeah mines a little weird, its sometimes accurate and sometimes not. First thing tomorrow morning im getting the new one and putting it in. The fact that Ford put "Normal" on the ect and oil pressure gauge was quite amusing when I first got the fox, seller told me as long as its within normal you're fine:shrug:

How would I install an autometer oil pressure gauge? ive heard a lot of guys put an ect,tach and oil pressure cluster on the dash of there foxes, wondering what's the cleanest way to do it?
 

5.0aintslow

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May 22, 2019
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just cracked old sending unit open, starting to realize this is just a glorified dummy light with a big old resistor to make a needle move. Ford engineers should've stuck to a dummy light lol
 

08GT500

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Jul 12, 2018
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Hi, Yup, gauges not up to par is a vast understatement. Here’s a Pic offline a SN member posted about as “right” as “right” can be. Pillar gauge mount, gauges exactly where they need to be...
8D773615-7D37-4689-AFF7-A7959A3D1E12.jpeg
 

96pushrod

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May 15, 2018
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Pillar pod, as stated above tends to be the cleanest way to do it. Kind of a pain in the ass to run with wiring (at least for an afr harness, oil pressure is easy) but worth it.

I’ve had the factory gauge drop and read all kinds of ways. Definitely not a gauge I’d trust to give the overall health of my engine.
 
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5.0aintslow

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May 22, 2019
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Morning

Just got the new switch in, fired it up and sure enough the needle jumped up 3/4 of the way at idle, and stayed still, no fluctuations. This is really relieving haha!
I found a cluster set, not pillar for sale near me, I think I'm going hold off until I can find a pillar set, think it looks best. How would you wire it in?? Just splice into the feeds from the sensors or cluster? Im sure I could look it up on youtube
 

08GT500

Active Member
Jul 12, 2018
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Hi, Glad to hear it was only the sender flaking out & not something much worse! Great input above to apply, AM, Summit, LMR, etc. sell pods, 2-1/16” backlit gauges, take your time, ask questions, do it right.
Good luck!
 
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