Golf Mk6 CAYD 1.6 TDi Bluemotion Oil Pressure Light flashing

[maddogphysics]

Had the car since just before Christmas 2022.
87,000 miles on the clock.
2011 registration.

Noticed a puddle of oil on the driveway a couple of weeks ago.
No lights on the dash and VCDS was clear.
Engine sounded fine.

After searching for the source, initially thought it was the turbo, but soon saw oil coming out of the oil pressure sensor at the back of the engine, near the top. Pouring out.

Purchased an OEM replacement and noticed that the wiring from the old pressure sensor was cut, the other end of the cut wire underneath a jubilee clip on one of the air intake hoses.
After fitting, and checking the oil level, which had never gone below the minimum anyway as I check every weekend, I started the engine.
Within 20 seconds or so, the oil lamp stated to flash, about 3 times, then go out for about 30 seconds and then start to flash again. This kept going until I switched off the engine.

There are NO warning beeps either.

Couldn't see any more leaks but I was concerned that maybe some damage had been done before I noticed the oil spill.

Off with the sump to inspect the bottom end of the engine.

Absolutely clean, no bits of metal anywhere, no signs of overheating or scorching.
Plastic baffle in place and untouched.
Took off the oil pump and pick-up pipe.

Pick-up pipe was dirty with bits of sealant in it and such. In fact the original sealant was overspilling into the sump and must have gone broken off into the filter over the last few years.

Pick up pipe is now clean, oil pump back on but do I need to do anymore checks whilst the sump is off?

Do you think the oil cooler needs checking?
The temp of the oil never really went above 90 degrees (MFD) anyway but I have noticed the engine coolant temperature doesn't reach 90 either...it varies quite a bit and is not stable (new thermostat?)

Thanks for taking the time to read.

[Crasher]

What is the VIN and the part number of the switch you fitted?

[maddogphysics]

I am thinking of finding out the actual oil pressure mechanically once the sump is back on.
Will give me a chance to take off the oil pressure sensor and find its part number...I really cant see the numbers, my eyesight is so poor now, sadly.

The vin of the car is: WVWZZS1KZBW328017

The varient is: ACCAYCX0 not the CAYD that I mistakenly thought it was.

Crasher, you actually fixed my Passat B6 almost 10 years ago...after the injectors were replaced under warranty by VW in Chesterfield, the VW technicians had replaced the vacuum pipes the wrong way around so the turbo stopped working!
You spotted that quite quickly. Thanks.

[Crasher]

WVWZZZ1KZBW328017.

A CAYC engine, the switch should be part number 036 919 081 D which is 0,3-0,6BAR and colour coded green. The VW specification is bizarre, they state

"Oil pressure when idling: at least 0.6 bar. increase speed. At 2000 rpm and an oil temperature of 80 °C, the excess oil pressure should be at least 1.0 bar"

The specification I am used to is 2 Bar at 2000rpm as a minimum and preferably 3 Bar.

[maddogphysics]

I eventually took the oil cooler off.

The oil side was blocked but with a bit of dish washer tablets, boiling water and lots of agitation, it finally cleared.
The coolant side looked like it had rusted, but aluminium doesn't rust so I don't know what it is.
Anyway, all cleaned and I'll start putting it back together over the weekend.
I will do a pressure test in VCDS and with a proper pressure testing kit...see how they match up.

I will keep you all informed.

[Crasher]

G13 coolant when it breaks down looks like rust.

[maddogphysics]

Well, put the car back together.

Still had the flashing oil light and now the flashing coil light.

EGR recirculation failed causing the flashing coil.

SO took the egr apart...filthy dirty, took out lots of carbon deposits so hopefully should sort the flashing coil...we'll see.

The oil pressure light...
Drained the coolant and oil.
Took off the oil cooler and realised there was no oil in the cooler but there was oil in the filter.
So I'm thinking maybe the oil filter has some sort of blockage.
I will take off the oil filter on saturday to investigate.

[maddogphysics]

Bought new oil pump.
Replaced it in the snow...strewth it was cold and wet under the car.

The oil cooler was blocked so considering gsf car parts to replace but not sure of their quality.

Can anyone recommend an online supplier of the oil filter housing and cooler rubber gaskets?
Thanks

My replacement HEX-V2 arrived today (replacement for my 10 year old vcds one).
Looking forward to playing with it

[Crasher]

We would use a Febi cooler

[mickeybo]

Ask yourself the 64 dollar question whats the first fall off point in the oil pressure system

[maddogphysics]

38954
Ask yourself the 64 dollar question whats the first fall off point in the oil pressure system

I did, many times.

Well, at least the EGR valve was cleaned.
The coolant system was flushed.
The oil pressure sensor and harness replaced.
Whilst waiting for the sumps silicon gasket to go off, took the time to re-seat the parking sensors...took the bumper off to remove a dead and bleached bumblebee inside one of the headlights and noticed two parking sensor fittings were broken.
The oil cooler replaced (I think this was the cause all along and maybe damaged the oil pump).
New oil pump fitted.
Still waiting to put it all back together but will delay a bit to watch Six Nations.

[maddogphysics]

We would use a Febi cooler

Thanks.

[mickeybo]

This problem should have been checked out at the first oil pressure fall off position

[maddogphysics]

This problem should have been checked out at the first oil pressure fall off position

I took it to a local garage to sort the oil leak and give it a service.
When I went to pick it up, the mechanic said there's good news and bad news...good news was the oil leak had been found and fixed, bad news being the had to fix the wiring harness for the oil sensor and when they did, the red warning light started "flickering".
I hate getting good and bad news!
The garage couldn't fit me in to find the problem for a couple of weeks but kindly took the car home for me...
Decided to do it myself even though I didn't have a clue as to what I was doing.
Got to give it a go though

[Crasher]

Warning light flickering? They flash at a predetermined frequency but they don’t flicker like in the distant past.

[maddogphysics]

Warning light flickering? They flash at a predetermined frequency but they don’t flicker like in the distant past.

Well, it comes on for a few seconds, maybe 5, then goes out for about 20 seconds, then repeats. No sounds.

Put it all back together with new "everything"...same.
However, when the car is warmed up, at about 70 degrees coolant, 60 degrees oil, the oil light stops repeating...until I press the accelerator and it comes back on again. Goes out if I let it idle.

Going to take the oil pressure switch out after rugby and check again the actual oil pressure.
Tried doing it with ross tech but car is using UDS protocol so will head over to the Ross Tech forum to find out how to do it.
I wonder?...I wonder?...maybe the software on the car is out of date?
Maybe the injector o-rings on the rocker cover need replacing? I do get the occassional whiff of diesel...

Straw is being grasped at the moments.

[maddogphysics]

Well, great win by Ireland. After a poor performance by England yesterday, I might change to being Irish as all my grandparents were Irish....on second thoughts, nah, I'm still hopelessly English.

Anyway, car now giving 7286 Turbocharger Boost control P2563 Implauible signal.
Will check vacuum and N75 tomorrow...bugger


Readiness: 0 0 0 0 0
Sunday,12,March,2023,18:02:23:05470
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 11 x64
VCDS Version: 23.3.0.0 HEX-V2 CB: 0.4631.4
Data version: 20230228 DS346.1
www.Ross-Tech.com

VIN: WVWZZZ1KZBW328017 License Plate:

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

Address 01: Engine Labels: 03L-906-023-CAY.clb
Control Module Part Number: 03L 997 557 T HW: 03L 907 425 C
Component and/or Version: R4 1.6l TDI H43 9982
Software Coding: 08114014032501080000
Work Shop Code: WSC 01357 011 00200
ASAM Dataset: EV_ECM16TDI02103L997557T 003003 (VW36)
ROD: EV_ECM16TDI02103L997557T.rod
VCID: I think I should not show this ID
1 Fault Found:


7286 - Turbocharger Boost Control Position Sensor Circuit
P2563 00 [101] - Implausible Signal
Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 141225 km
Date: 2040.14.24
Time: 16:53:16


Engine RPM: 780.50 /min
Normed load value: 27.8 %
Vehicle speed: 0 km/h
Coolant temperature: 31 °C
Intake air temperature: 13 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 14.569 V
Unlearning counter according OBD: 40
Charge air pressure actuator: acknowledgment-ANG_BPA[0]: 40.021 %
Charge Pressure Actuator: activation-ANG_SP_BPA[0]: 85.001 %
High press turbocharger actuator: activation-CTL_LIM_BPA[0]: 84.998 %
High press turbocharger actuator: actual uncond volt value-V_BPA[0]: 1.870 V
Turbocharger boost control: offset open-V_BPA_BOL[0]: 0.498 V
Turbocharger boost control: offset closed-V_BPA_TOL[0]: 3.477 V
High press turbocharger actuator: status-LF_STATE_BPA_DISP[0]: 76




Readiness: 0 0 0 0 0

[Crasher]

I would suspect the turbo actuator diaphragm is split.

[maddogphysics]

Ok, just done the mechanical oil pressure test.
Results are for a cold engine.
Idle 1.5 bar
2000rpm 1.75 bar

Took vacuum tube off actuator and drew the air out. It kept the pressure on my tongue for a while and when i let it go could hear something moving.
Going to warm up the car now to get more oil pressure tests.
Thanks for replying C


So, 15 minutes later...

Idle 0.6 bar
2000rpm 1.5 bar

Noticed also the pressure sensor is not OEM.

Will order one and stop this faffing about.

[Crasher]

That is only just good enough, the switch you need is 036 919 081 D which closes at 0.3>0.6Bar

[maddogphysics]

Might also need to change the 4/2 thermostat as the coolant didn't get above 60 degrees and the oil temp ditto.

[maddogphysics]

Ok

So I have now sorted the problem.
After putting in a new OEM pressure sensor, the red flashing light stayed on.
I traced the wire back to the ECU and found bare wire where it was rubbing at a bend.
Replaced the wire and light went off at last.
Was getting under/over boosf in the turbocharger, P0299 and P2563 codes...eventually cleaned boost pressure sensor on the intercooler outlet pipe with brake cleaner and all the codes have disappeared.
I did use a vacuum pump to check all the pipes and the N75, etc which showed everything was working.
I had taken the air intercooler pipes on and off so many times, like a brides nighty, to sort the oil cooler so must have affected the sensor as the faults had come on after all the messing around.

Now must change the 4/2 thermostat...maybe over Easter.
Happy now.
Thanks for your help C