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If you missed previous threads my engine is blown. Can anyone help me out by explaining to me exactly how the oil pressure gauge functions? where is the information coming from and how is it calculated? I know now thats its more or less useless but this information would help me with my warranty battle
 

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^ No ... that would be the oil temp gauge.

The oil pressure gauge uses a electric sender mounted on the backside of the engine ... below the intake manifold. Looking at the oil filter, the sender is at roughly the 10-11 o'clock position.

Because it is electric, there is some delay and the OE 'gauge' isn't that accurate to begin with. By the time there is a oil pressure problem, it is too late.
 

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The "sender" you are talking about mounted in the side of the engine block below the intake is just an "idiot light" switch. It triggers the low oil pressure light on the dash when the pressure in the system falls below 7-10 psi.

I have had mine off and checked it ,and it is not a potentiometer it's just an on-off switch.

The ECU looks at that switch to see if there is "ANY" oil pressure and then looks at engine speed and moves the needle on the gauge.

I have a real oil pressure gauge in my car and the factory gauge does not even come close to reacting to the "Real Engine Oil Pressure" like the mechanical gauge .

To answer the origional question, as long as the Idiot light on the instrument cluster was not on you had at least 7 psi of oil pressure, other than that you have no way of knowing how much pressure you really had.
 

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They programed the ECU to look at engine speed and move the needle as engine speed goes up and down. Makes it look like the gauge is doing something. If you watch the needle, when the engine is at idle it reads in the same place it always reads at that same engine speed (on my car about 3 needle widths below the middle of the gauge). When the engine is cold the real pressure is between 75-80 psi. When it is hot after about 20 minutes on the track and an oil temp above 230degF at idle the real oil pressure is between 25-30 psi but the factory gauge reads the same as before. It's just an idiot light with a pointer.

The oil temp gauge is also controled by the ECU and it looks at water temp and duty cycles (how hard are you driving and for how long) my factory gauge reads mid scale within 5 miles of my house every morning on the way to work, it reads the same with oil temperatures as low as 100 deg F and as high as 230 deg F. At the track I have had the oil temp as high as 260 deg F and the gauge only reading at 3/4 scale and other times the gauge is pegged HOT when the oil is below 240 deg.

I think I would really rather have the little coin storage cubby, it would sure be of more use.
 

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Any way to hot wire those gauges to do something real? like read a real sender unit?
 

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ok, heres what im not understanding, why the hell does everyone keep saying the oil pressure gauge is fake, ever time ive read something about an engine blowing up do to loss oil pressure and they always say the oil pressure gauge goes to zero, doesnt that mean somthing?? if you gauge is going to read zero when the pressure actually does drop and the engine pops, then doesnt it do its job when you put the gas through the floor and the pressure needle rises. im sorry but i dont think SVT would put a fake gauge in any of there cars, just doesnt make sense.
 

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I can't believe that they would do that........an "eye candy" gauge in an SVT? I dunno.......
 

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All I am saying is I would never trust an oil pressure gauge that is not attached to a sensor that is actually LOOKING at the oil pressure in the engine or an oil temp gauge that does not have a sensor that is actually touching the oil somewhere. THE SVTF has neither.
 

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second thought - are there any aftermarket guages that would fit in to the same spots where said oil guages are? I like the look of it the way it is, but if other, more accurate guages could be fit in there with out modification, other than to install 'em, I'd consider it.
 

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if you read the service manual it explains. The oil pressure gauge reads the oil pressure switch, if its in an "acceptable" state, then it reads the RPM to move the needle all over to make it look like its doing something.

But the oil pressure switch will over ride the RPM if it goes to a
"danger" state and move the needle down to the bottom and turn on the idiot light.

Thats why when the engine blows the needle drops... its a gimick, even the ford service manual describes it as such. Same as oil temp.
 
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