P06DE and low oil pressure warning

[jonnybump]

Hi all, I have a 2014 CX-5 2.2D with 115000 miles and yesterday my car threw the above code with error message stating "Low Oil Pressure" and entered limp home mode. I immediately pulled over and stopped the car, thinking the worst (that the oil pump chain had snapped as many have had an issue with), called Green Flag and they sent out an engineer.

The engineer plugged his diagnostic machine in and it showed a P06DE error code, he cleared the code and started the car. He said the pump was definitely working and the engine was running fine, oil level was good. He said it would be fine for me to drive home. I drove it back, taking it easy, and the car entered limp home mode three times, with the same error message. Every time, I pulled over and turned the car off which reset it.

When I got home I plugged my laptop in and ran Forscan to check the oil pressure reading - at hot idle it was showing 120kpa. Is it me or does that seem low-ish? When I drove the car this morning I left Forscan connected and ran the oscillope, it showed cold idle oil pressure of 155kpa. When accelerating, pressure increased to 250-350kpa, then when changing gear the pressure dropped sharply to 80kpa, bouncing back up to 120kpa almost instantly.

Oil was changed 3000 miles ago, do you think this could be something to do with the oil solenoid valve that controls the dual stage pump? P06DE is described as "Engine Oil Pressure Control Circuit Stuck On".

Thanks
Jon

[jonnybump]

UPDATE - I plugged Forscan in to monitor the drive home from work. Not far into the journey is quite a steep hill that leads to the motorway. Halfway up the hill the car returned a red warning triangle and advised to get the car checked by the garage. It did not throw the low engine pressure error - the DTC stored in the memory is P06DE, same as yesterday. Everything remained normal, except looking at the data, the ENGINE OIL PRESSURE DUTY CYCLE, which is normally around 60% dropped to zero for the remainder of the journey.

[Anchorman]

Try changing the oil and resetting the oil data - this must be done via the test wire under the bonnet.

[jonnybump]

I will be changing the oil, but this morning I drove the car in to work and the warning came up almost instantly (Low Oil Pressure P055F Engine Oil Pressure Out of Range). The oscillope showed that the oil pressure was dangerously low - 80kpa and at times dipping slightly lower than that. I've had to abandon the car, I didn't want to cause any lasting damage.

I'm going to drop the sump and see if the oil pickup/strainer is clogged, I've heard some people have had that issue with this particular model. Not what I need just before Christmas! 

[Anchorman]

I will be changing the oil, but this morning I drove the car in to work and the warning came up almost instantly (Low Oil Pressure P055F Engine Oil Pressure Out of Range). The oscillope showed that the oil pressure was dangerously low - 80kpa and at times dipping slightly lower than that. I've had to abandon the car, I didn't want to cause any lasting damage.

I'm going to drop the sump and see if the oil pickup/strainer is clogged, I've heard some people have had that issue with this particular model. Not what I need just before Christmas! 

Probably a good idea.  Apparently new ones are very cheap so if it is clogged it might be easier.

[jonnybump]

They're on ebay for £50 but my Mazda dealer have ordered one in for me for £35.54. I will have to do the work at my work premises so will have a look on Tuesday after they shut and will post my findings!

[Anchorman]

They're on ebay for £50 but my Mazda dealer have ordered one in for me for £35.54. I will have to do the work at my work premises so will have a look on Tuesday after they shut and will post my findings!

Have you got the instructions for resetting the oil data?

[jonnybump]

I havent, no. I always used Forscan. What's the other option? While I'm working on the car I'm thinking of inspecting/changing the injector washers. I've heard these are also a weak point with this engine, failing then allowing exhaust fumes to mix in with oil which creates carbon deposit build up.

I've checked the workshop manual and it doesn't seem a huge job - have you ever changed them?

[Anchorman]

I havent, no. I always used Forscan. What's the other option? While I'm working on the car I'm thinking of inspecting/changing the injector washers. I've heard these are also a weak point with this engine, failing then allowing exhaust fumes to mix in with oil which creates carbon deposit build up.

I've checked the workshop manual and it doesn't seem a huge job - have you ever changed them?

Not on the Mazda no but I’ve got some experience with Toyota 2AD engines. It’s sometimes easier to wait until they go as they tend to be loose. Getting them out without breaking them can otherwise be a challenge but you can at least try. 

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[jonnybump]

OK I had a go at this today after work...and where do I start!

Firstly the oil sump pan is an absolute nightmare to remove with all the liquid gasket/sealant. Took over an hour but managed it.

Secondly I diagnosed that the strainer was full of carbon pieces, it's no wonder the oil pressure was so low. The problem that I had then was that the strainer is bolted to the SIDE of the oil pump which in turn is bolted to the oil pump balancer. Without removing the oil pump from the balancer it is impossible to remove and replace the strainer. I did not have the confidence to remove the whole unit so ended up using a thin but relatively strong bunch of wires and wiggled them around inside the strainer to loosen up as much carbon as possible. I then used an aerosol degreaser sprayed into the strainer to flush the particles out. Trust me there were loads, I could have made a lump of coal with what came out... And there were bits in the sump too which I completely cleaned.

The design of the strainer not being easily changed is ridiculous, unless someone knows of an easier way to do it?

Anyway, I put it all back together, filled with fresh oil and new filter and it's now running an oil pressure of 160kpa at 60deg c. I haven't driven the car long enough to test it out long term, and I don't really want to until I've changed the injectors which I will be doing next week.

[Anchorman]

OK I had a go at this today after work...and where do I start!

Firstly the oil sump pan is an absolute nightmare to remove with all the liquid gasket/sealant. Took over an hour but managed it.

Secondly I diagnosed that the strainer was full of carbon pieces, it's no wonder the oil pressure was so low. The problem that I had then was that the strainer is bolted to the SIDE of the oil pump which in turn is bolted to the oil pump balancer. Without removing the oil pump from the balancer it is impossible to remove and replace the strainer. I did not have the confidence to remove the whole unit so ended up using a thin but relatively strong bunch of wires and wiggled them around inside the strainer to loosen up as much carbon as possible. I then used an aerosol degreaser sprayed into the strainer to flush the particles out. Trust me there were loads, I could have made a lump of coal with what came out... And there were bits in the sump too which I completely cleaned.

The design of the strainer not being easily changed is ridiculous, unless someone knows of an easier way to do it?

Anyway, I put it all back together, filled with fresh oil and new filter and it's now running an oil pressure of 160kpa at 60deg c. I haven't driven the car long enough to test it out long term, and I don't really want to until I've changed the injectors which I will be doing next week.

Good on you for having a go and it sounds like you’ve had the right result. I’m a mechanic by trade so pulling an engine to bits doesn’t phase me but what might have stopped me is how the oil pump is fixed. Occasionally you need the timing cover off and in that case the engine out so if that were the case I’d probably have done what you did.  I’ve probably got the instructions from the manual somewhere.

[Jonno21]

OK I had a go at this today after work...and where do I start!

Firstly the oil sump pan is an absolute nightmare to remove with all the liquid gasket/sealant. Took over an hour but managed it.

Secondly I diagnosed that the strainer was full of carbon pieces, it's no wonder the oil pressure was so low. The problem that I had then was that the strainer is bolted to the SIDE of the oil pump which in turn is bolted to the oil pump balancer. Without removing the oil pump from the balancer it is impossible to remove and replace the strainer. I did not have the confidence to remove the whole unit so ended up using a thin but relatively strong bunch of wires and wiggled them around inside the strainer to loosen up as much carbon as possible. I then used an aerosol degreaser sprayed into the strainer to flush the particles out. Trust me there were loads, I could have made a lump of coal with what came out... And there were bits in the sump too which I completely cleaned.

The design of the strainer not being easily changed is ridiculous, unless someone knows of an easier way to do it?

Anyway, I put it all back together, filled with fresh oil and new filter and it's now running an oil pressure of 160kpa at 60deg c. I haven't driven the car long enough to test it out long term, and I don't really want to until I've changed the injectors which I will be doing next week.

Kudos to you for doing this. I'm not mechanically minded so would be an absolute nightmare for me. However, give me a CMU firmware upgrade to perform and I'm all there.