Low oil pressure warning light CEL solved 2006 Jetta BRM 1.9

A few weeks ago my Jetta warned LOW OIL PRESSURE, STOP ENGINE NOW and chimed at me.

I took the car to Auburn WA VW and we agreed to change the oil to a VW approved 505.01 motor oil.

That solved the problem, as the CEL has not sounded in over 3 weeks. And the car seems to handle better.

The manual for my 2006-2007 Wolfsburn Jetta specifies only 505.01 motor oil. I speculate that when I changed my oil about 3 months ago, that I used the discount motor oil I had become accustomed to using in my 2.2L Subaru engines. After several weeks, I speculate that the oil "thixotropy" broke down enough that it tripped the low pressure sensor in the engine. I have noted in the past that as oil breaks down, its viscosity and its "thixotropy" becomes reduced.

The engine was low by 1 quart of oil as well. But even after I topped it off, and rebooted the car computers by leaving the battery unplugged for a few hours, the code reappeared in the vehicle. Again I am speculating that the extra quart of oil did not reconstitute the "body" of the oil sufficiently to prevent the low pressure signal from being generated.

Sir/Ma'am, I strongly suggest that if you're going to dabble in the ownership experience of the Volkswagen brand and diesel product specifically that you read and re-read your ownership manuals.

Using the "discount motor oil" that was earmarked for your Subaru can/will lead to severely expensive camshaft and valve train wear on the unit injector engine.

Also, a simple internet study of newtonian and non-newtonian fluids with emphasis on thixotropic/rheopectic definitions will help you understand a bit more about the dynamics of a multi-grade motor oil.

^^^+1 on the camshaft damage. The PD cam barely survives with the correct oil.

Should also worry for the turbo..

aheng said:

The engine was low by 1 quart of oil as well. But even after I topped it off, and rebooted the car computers by leaving the battery unplugged for a few hours, the code reappeared in the vehicle.

Click to expand...

What "code" was that? AFAIK oil pressure on a BRM is not monitored by the ECU so a code can not be set for low oil pressure.

The term "thixotropy" does not apply in this case, the proper term is "Viscosity".

https://en.wikipedia.org/wiki/Viscosity

Quite simply you put oil of the wrong spec and viscosity in your engine causing a low pressure indication and turning on your low oil pressure light.

In your owners manual for a 2006 BRM the correct oil is VW 505.01 5W40. The 505.01 oil the dealer sells is actually the wrong oil for your car is 5W30.