2010 Passat TSI with oil pressure light on

Hi there.

Got this Passat European version on the shop with oil pressure light on after 1500 rpm. It has 46.000 km/28,750 mi. The light blinks three times and then switches btw watch and warning light.

Change oil pressure sensor for OEM part and no results. Connected Pico Scope to analyse the pressure curve with transducer and fluctuates betweeen 1.75 at idle to 3,0 bar at 2000 rpm. Sensor is calibrated to 1,2 to 1,6 bar. The aceleration curve shows smooth incrementation on aceleration and and smooth on deceleration showing no losses or clogged system.
Changed the oil to 5W40 and still no results. Open the oil pan and checked the strainer to see any debris and it was clean. It has no knocking or any weird sound comming from engine when light is on.
I believe this car has no PWM oil valve controler.

Please help me out here.
Thank you

Hi and welcome.

This does not belong in Forum Support & Feedback. Moving to Car Repair Support.

Please post an Auto-Scan so people can see exactly how this car is equipped and configured.

-Uwe-

Hello Radovan,

We received the Support email with Auto-Scan related to this vehicle however the thread should be located in our Car Repair Support section. I'll move it there.

In the meanwhile, even though there aren't any fault codes it couldn't hurt to post the scan. Doing so will allow forum members to see the VIN to obtain the engine code and similar.

Your issue may be mechanical even though he pressure appears to be OK. If you haven't done so already I would make sure you replaced the filter with a VW part and make sure the O-Ring sealing areas of the spring loaded tube beneath it isn't faulty. That "tube" is item # 16 in this temp screen shot:

https://media.trillian.im/media/?m=...RbATWWFKCpfzVl13vcf9MgFbr6g520Jma/0tz18QW2A==

.. and this website has an actual photo: https://www.ecstuning.com/b-genuine-volkswagen-audi-parts/oil-filter-retaining-post/06j115679e/

Additionally, I wouldn't waste that new oil but you might want to drain it into a clean catch pan and put something heavy (like a 50 Weight) in there to see if that masks the issue or not. You could alternatively add a thick additive to the existing oil but I wouldn't want to leave it in there long-term if this turns out to be an electrical problem.

Edit, I just realized Uwe moved this thread as I was drafting.

I already use an oil thickner SAE 90 - honey type and the problem persisted. Install OEM fileter and checked the valve/ spring under the filter and no visible problems. Also if I had a problem on that check valve I would have an oil leak when I unscrewed the sensor, right? Correct me if I´m wrong please. I might start to think is an electrical problem.

Hi Radovan,
Is this definitely a low oil pressure problem? Does the bonnet switch work?
Regards HMC

Please check the crankcase ventilation on the valve cover. I know that sounds strange, but if the membrane leaks, there may be a slight drop in oil pressure. I had this case very often during my time at VW and Audi. Of course there are many other possible causes. It is just an idea that may be quick and cheap to fix. I have to say, in most cases the membrane was not so torn that there was a noticeably uneven idling yet.

Hello,

Here is a silly question, have you checked the oil pressure with a mechanical "Oil Pressure Gauge"?

I have a 2009 Passat 2.0L with a CCTA engine, every once in a while the oil pressure waning message/light came on.
So I used an old school mechanical gauge I have had forever and I found that there was in fact low oil pressure. I replaced the oil pump and I use 5W40 oil now, seems better...

You may not have low oil pressure, but I would want to verify the readings and use a mechanical gauge, use one that is of decent quality, with a long enough hose so that the gauge can be taped to the windscreen so you can see it while driving.

I would check the oil pressure cold, warm, idle cruise, full throttle .. etc

Also as a rule of thumb, newer engines with one oil pressure switch do not have a oil pressure reducing system, typically the engines that do use this systems will have two oil pressure switches.

Let us know what you find,

drpeter

found the problem

DrPeter said:

Hello,

Here is a silly question, have you checked the oil pressure with a mechanical "Oil Pressure Gauge"?

I have a 2009 Passat 2.0L with a CCTA engine, every once in a while the oil pressure waning message/light came on.
So I used an old school mechanical gauge I have had forever and I found that there was in fact low oil pressure. I replaced the oil pump and I use 5W40 oil now, seems better...

You may not have low oil pressure, but I would want to verify the readings and use a mechanical gauge, use one that is of decent quality, with a long enough hose so that the gauge can be taped to the windscreen so you can see it while driving.

I would check the oil pressure cold, warm, idle cruise, full throttle .. etc

Also as a rule of thumb, newer engines with one oil pressure switch do not have a oil pressure reducing system, typically the engines that do use this systems will have two oil pressure switches.

Let us know what you find,

drpeter

Click to expand...

Hi there

Thank you for all the help I got, but the problem was solved by exchanging the oil sensor for a new part. Seems like even a brand new part previously purchased from dealer was questionable.

All soved!!! Thank you.