Oil Pressure Sensor Location/Type

Hello, I am wanting to replace the oil pressure sensor in my C3 as I am hoping that it is the cause of an intermittent oil pressure warning at low revs.

Now I'm no mechanic but I thought I had located the oil pressure sensor on what looks to me to be the oil pump sandwiched between the engine and the gearbox.

So I put my reg number into the euro car parts site and bought the following sensor

https://www.eurocarparts.com/ecp/c/Citroen_C3_1.4_2005/p/car-parts/fuel-and-engine-management/engine-parts/engine-management-switches/..

only to find that when I got home that what I believe to be the oil pressure sensor in the car has 2 pins whereas the sensor I bought only has one pin.

so, have I bought the wrong part or have I not actually located the sensor in the car.

Any help gratefully received.

Many thanks, Lee

Hi Lee

It may be better to do this by VIN because changes are made over the years to C3 parts.

PM the VIN and I can look it up for you.



Number 7 is the engine oil pressure sensor

Many thanks for your response.

The VIN is VF7FCKFVB 27106114.

Cheers, Lee

Hi Lee

Your VIN comes back as part

1131.C5

which is available here and is the number 7 on the diagram above. It is a standard Febi part used on many different makes of car.

There is only one wire going to the pressure switch anyway. When there is no oil pressure that wire is grounded through the metal part of the switch body making a circuit, causing the warning light to come on. When there is oil pressure the circuit is broken and the light goes out.
The "other" switch you had might have had a redundant (extra) earth so it could be mounted in a plastic housing. That would be why it had two connections but still operated. I'm not saying it operated correctly, I don't know it's serviceability.

Well thanks to your help I have successfully changed the oil pressure sensor

Unfortunately, I still have the same problem of the oil warning going off at idle and low revs.

Any ideas? Would changing the oil filter be an idea? Or maybe an oil change? Or could it genuinely be a low pressure problem and the oil pump not working properly?

Many thanks, Lee

I couldn't tell you if the switch is on the pump or gallery side of the filter.
If its on the gallery side, problems with the oil filter would cause low pressure.
If you do not know the history of the filter I would change it on spec. There were initial problems with the Purflux filters collapsing under the oil pressure. It could be the wrong type of filter there are two types. One just looks like a regular filter and the other has a little protrusion with an oring around it. You'll need to see if C2driver52 can get you the correct part number for your engine.
If the switch is on the pump side, then either the pump is worn (very rare) or there is something blocking the inlet mesh. You would need to drop the sump pan to investigate.
Changing the oil filter is the quickest, and simplest to start.

The docs say for that VIN, use this 1629084080 oil filter

A filter and oil change (Total Quartz 7000 semi synth) can never do any harm and you get to look at the state of the black stuff drained.

Well many thanks for your help chaps replacing the oil filter and changing the oil has solved the problem.

Cheer,s Lee