Oil pressure switch location

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937carrera
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Re: Oil pressure switch location

Post by 937carrera »

One other thought, did you check the wiring back to the clocks ?

The sender /switch is closed until pressure is present. From the fact that the light goes off after 5 seconds it seems that the instruments have an initial timing function which is why the light is extinguished after ~ 5 seconds. It will come on again if pressure drops and the switch closes.

Maybe it's worth starting the car with wiring removed, running at a speed at which the light would not illuminate and then earthing the wire at the sender unit. The warning light should come on - and perhaps the buzzer as well ??
Mike_Galv
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Re: Oil pressure switch location

Post by Mike_Galv »

Hi guys, sorry to drag up an old thread but I'm getting an oil warning light on and off (sometimes it's fine for like a month then one day I'll get the buzzer and the warning light for about 5 minutes, then it goes off and doesn't come back on for another month or so). After reading this thread and a few others I'm now concerned about driving the car incase it is the oil pump. So I managed to get hold of an oil pressure tester, I just have a few questions on the procedure and what I'm actually looking for.

So I take it I remove the oil pressure switch (front, top right of the engine with a green connector), select the relevant fitting for the tester and connect the tester in place of the pressure switch (while the engine is cold so no oil is high up in the engine and likes to leak out). Then I assume I start the car, check for leaks quickly and then see what reading I'm getting.

What sort of pressure should I be looking for? Do I need to run the engine up to temp (take cold and warm reading?). And do I need to be taking readings at different rpm and if so what pressures am I looking for?

I have read elsewhere that a bouncy needle could be a concern also but for a different issue (or that it could be an unreliable pressure tester), what's the general consensus on that one?

Sorry it's a bit long winded, hope someone can shed some light for me.

Thanks in Advance!!
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937carrera
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Re: Oil pressure switch location

Post by 937carrera »

Quick answer - You've got the right idea about the test procedure.

Oil pressure reduces with temperature, so you need to take readings as the oil temperature rises. As a guide at 80 degrees C you should have over 0.7 bar at tickover and at least 2 bar at 2000 rpm. Will probably be 5 bar when cold, but of course it depends what oil you are using too
Mike_Galv
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Re: Oil pressure switch location

Post by Mike_Galv »

Thanks for that! Is that 5 bar at 2000 rpm when cold I take it? Also, what would I be looking for cold at idle?

I'm using Castrol Magnatec 10W40 Synthetic. I believe that's the correct oil for the car.

One last thing, the gauge I'm using goes round to about 28 bar by the looks, the readings im looking for all look to be very low down the gauge... dunno how easy that's going to be to read... does that sound right?
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937carrera
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Re: Oil pressure switch location

Post by 937carrera »

Oil sounds OK.

Don't worry about pressure when cold, it'll be plenty, it's hot when you'll have an issue. The 5 bar reference was cold.

Yep, you'll only be using a small part of the gauge capability. Not as granular, but better than nothing. :D
Mike_Galv
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Re: Oil pressure switch location

Post by Mike_Galv »

Just tested the pressure this morning, got just under 2 bar at idle between 80-90 degrees and just under 4 bar at 2000 rpm. Already got a new sensor to put in the other week while ECP has a discount on so do you guys think it's safe to assume it's just the sensor that's the issue?
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937carrera
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Re: Oil pressure switch location

Post by 937carrera »

That would be my conclusion too, if the wiring is OK :)
Mike_Galv
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Re: Oil pressure switch location

Post by Mike_Galv »

Awesome, thanks for all your help!
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