1.4 MPI - Oil Pressure Switch Guide

[Taylor93]

I have my hands on a 1.4 MPI Estate (51 Plate, Engine code AQW) and as it need a bit of work, I have decided to write a few guides to help fellow Briskodians with some of the issues this engine suffers from. First one is for the Oil pressure Switch, nice and simple start.

 

Just as a disclaimer, i accept no responsibility if you cause any damage to your car while following this guide, ensure you are confident in what needs to be done prior to starting the task.

 

The Fault:

The plastic potting in the Oil pressure sensor breaks down and allows pressurised oil to leak through the sensor and out of the connector itself. 

 

The Symptoms:

Lower oil pressure, depending on how bad the sensor fails it could also flag an Oil pressure warning Light on the Dash cluster. (it didnt in my case). Oil leak/drip on the drive way, it was running down from the sensor down the gear box and then dripping, it looked like an oil leak from the rear of the engine but wasnt. With the engine running i placed a clean rag on the underside of the sensor/connector housing to find oil collecting, disconnecting the sensor should allow for more flow out if its suspected. Oil marks also visible on the engine block from that point downwards.

 

The Fix:

 

Tools:

1) 1x Oil Pressure sensor 047-919-081B (£5.80 from my local TPS, check it does have the copper Washer too)

2) 1x 24m Spanner

3) 1x Screwdriver etc to unclip the connector

4) Drain pan/bucket , I did this on a stone cold engine, so had minimal oil flow/spillage, but its worth using a bucket to catch any drops of oil.

5) Degreaser & Rags

 

 

 

Start by identifying the Oil Pressure sensor, it is located near the bell housing on the front side of the engine. (See Number 1 below). Then unclip the connector. For better access i also unpluged the Camshaft sensor (Number 2) so i didnt snag the wiring. I then liberally sprayed the area with Degreaser and wiped any oil away with the rags. Also clean the connect on the loom as this may have some oil in it too.

 

 

Once is unplugged, undo it, the old one on this vehicle was not OEM but had still failed. Again i was working on a cold engine (so the oil was thicker) Work Quickly to reduce the chance of any oil leaking, I removed it and its old washer (dont reuse), Then i plugged it with a rag to stop any leaks, followed by fitting the new sensor ensuring the copper washer was fitted. I made sure it was tight, however those who want to know it is Torqued to 45NM

 

Then plug the connector/s and wipe any oil spillage away. 

 

 

Once completed, run the engine up to temperature and check if the oil leak/warning light persists also top up the oil if required.

 

Tidy up and have a brew

 

FYI here is the old sensor and you can see the oil pooling inside the connector housing

 

 

 

Please let me know of anything ive missed

[Breezy_Pete]

Thanks for making the guide, nice work. :clap:

 

 

Torque setting for the switch appears to be different for different engines, according to Haynes? I realise this guide is aimed specifically at the MPIs, but it is basically the same procedure for any engine, give or take the exact position of the switch on the engine, so could be applicable to all Fabias.

 

25Nm on the 1.2 engines and the 16-valve 1.4s for example; and only 20Nm on diesels?

 

Not saying Haynes is necessarily right, and I can't find a figure at all for the 8-valve 1.4 petrols in there. Where did you find the 45Nm figure? Autodata?

[Taylor93]

Thanks for making the guide, nice work. :clap:

 

Not saying Haynes is necessarily right, and I can't find a figure at all for the 8-valve 1.4 petrols in there. Where did you find the 45Nm figure? Autodata?

 

Thanks I plan on writing one up for changing the Timing Chain too.

 

Regarding the value, I have obtained it from a Skoda Workshop Manual for the engine. 

 

But You are indeed correct:

 

1.2 6/12V = 25 NM

1.4 8V = 45 NM

1.4 16V = 25 NM

1.9 8V SDI/TDI = 20 NM

 

I dont know about the 1.4 TDI or the 2.0 8V Petrol

[Breezy_Pete]

Nice one. I guess the switch part number may not be the same across the board either.  If you want, I'm happy to photograph the switch locations on 1.2 AZQ engine and 1.4 BBY and add in, or pass to you to add in if you want? Part numbers should be easyish to check for other engines too. 

 

1.4 16V BBY engine, oil pressure switch (PN 036919081D) location couldn't really be any more accessible:

 

 

And here it is in the same spot (and same part number 036919081D) on the 1.2 12-valve AZQ-code engine head:

 

[Toxicvrs]

Nice one. I guess the switch part number may not be the same across the board either. If you want, I'm happy to photograph the switch locations on 1.2 AZQ engine and 1.4 BBY and add in, or pass to you to add in if you want? Part numbers should be easyish to check for other engines too.

I've got a photo of AWY one

[Taylor93]

Nice one. I guess the switch part number may not be the same across the board either.  If you want, I'm happy to photograph the switch locations on 1.2 AZQ engine and 1.4 BBY and add in, or pass to you to add in if you want? Part numbers should be easyish to check for other engines too. 

 

again your correct, the Oil Pressure sensor locations vary, the 1.4 16V it is near the EGR at the front right corner of the cam cover.

 

 

The main reason i wrote this was after a discussion with a friendly Skoda tech the other year, he informed me that they fail on the 1.4 8V more than on any other engine

 

This is the 2nd one ive come across... out of two 1.4 8V's :P

[Breezy_Pete]

They've all got moving parts, whatever the engine, but I guess the MPI's version may have been a bit under-engineered for the job if it is indeed a different part number to other engines? (Edit: it is, and it has a bigger thread diameter and pitch, M16 x 1.5, than the ones with lower torque settings. It's M10x1 for the other petrol ones, so that makes sense that they would need less grunt. Your part number seems to fit the following engine codes: ARV,AQV,ATY, AME,AQW,ATZ, AZE,AZF).

 

Apart from it leaking massively, I can't  see that a leaky/non-working switch can actually change the oil pressure; only fail to give pressure warnings, or more likely, give false warnings?

[Taylor93]

They've all got moving parts, whatever the engine, but I guess the MPI's version may have been a bit under-engineered for the job if it is indeed a different part number to other engines? (Edit: it is, and it has a bigger thread diameter and pitch, M16 x 1.5, than the ones with lower torque settings. It's M10x1 for the other petrol ones, so that makes sense that they would need less grunt. Your part number seems to fit the following engine codes: ARV,AQV,ATY, AME,AQW,ATZ, AZE,AZF).

 

Apart from it leaking massively, I can't  see that a leaky/non-working switch can actually change the oil pressure; only fail to give pressure warnings, or more likely, give false warnings?

 

If its a hole in the block on the pressurised side, your going to loose some oil pressure after that point.

on my first MPI it was indeed giving a false failure. said i had no oil pressure, when infact i did but the sensor was leaking.

[Breezy_Pete]

If its a hole in the block on the pressurised side, your going to loose some oil pressure after that point.

on my first MPI it was indeed giving a false failure. said i had no oil pressure, when infact i did but the sensor was leaking.

Can't argue with that.

[midoualy]

And the sensor doesnt leaking ... i went to 3 garage and all of them are not sure where is the problem , some say i want to open motor other say its from pomp !!!! I dont know what should i do any help guys and thnx a lot

[Taylor93]

If you have replaced the sensor (very cheap and simple) and it is still flagging an issue then it could be that your oil pressure is infact low.

If you can, get a gauge and screw it into the oil pressure switch location. At 2000rpm with oil at 80 degrees Celsius there should be 0.2MPa of pressure or approximately 29PSI.

If you test it and it is less than 29 PSI the oil pump may have failed or the oil pickup or pressure relief valve maybe blocked/stuck.

If it is more that 29PSI then id look at the engine bay wiring

[rar_balazs]

Hello,I have a fabia MK1 1.2 with BME engine code.

I had the valves fixed on piston 2,  but now betwen 1000-2000 rpm I am losing the oil presure,I already changed the oil presure sensor.The car is losing oil presure just when the engine is hot.If the engine is cold the oil pressure is ok.

Can somebody help me?

 

Thank you.

[Breezy_Pete]

Take it back to whoever fixed the valves and say "please fix the oil pressure problem that wasn't there before your work".

[rar_balazs]

Hello, can somebody help me?I changed the oil pressure sensor on a fabia mk1 1.2.

But the light still comes on betwen 1000 and 2000 rpm ,just when the engine is very hot.If I unplug the soket from the sensor and I rec the car over 2000 rpm the light comes on.Wht could be wrong?