Low Oil Pressure light and car dies..

Hello everyone, I have been researching on the topic for a while now and seems like the problem could be a few things but I kinda want to narrow them down before I start towing my car to a mechanic.


2006 Jetta TDI



Short version of the story is..
Drove for about 20min, suddenly low oil pressure light goes off. I am literally 5 blocks away from my house and decided to see if I make it. 2 blocks go by my RPM go down and car shuts down, everything turns off. Manage to pull over to the side. Check oil, all good. Just changed it about 2 weeks ago. Try to start it but it just makes the cranking sound and the lights on my dash keep flickering. Thinking maybe its the battery cuz car has been hard to start for a few weeks now and a few days back my negative terminal had corrosion so i cleaned it and it was starting way better after that. Got a friend to come by to jump start me. It worked, the car started but also with a few too many cranks and dash board flickering. Decided i have 3 more blocks to go to get to my house i go for it. 2 blocks up car dies again after low pressure oil light comes on. I pull over do the whole jump start thing and finally make it home. Given this information I am not that car savvy but I just want to get a clearer idea what is happening here. Next day I decided to charge the battery and it was showing 13.7V and decided to start it up and the oil pressure light came on again and this time i just shut it down myself. I really hope i didnt fk up the car even more with driving those few blocks. Also I have changed my alternator a year ago. Any ideas what this all could be?

I believe the ECU is programmed to shut the car off when the oil pressure is too low. This is actually a good thing, as it prevents catastrophic failures. Some possibilities might include:
1. Your oil pressure is actually too low. Oil pump problems are a possibility.
2. The oil pressure sensor has failed in a way that causes it to read incorrectly low
3. There is something wrong with your engine wiring harness

What does your VCDS tell you? You do have one, right?

sptsailing said:

I believe the ECU is programmed to shut the car off when the oil pressure is too low. This is actually a good thing, as it prevents catastrophic failures. Some possibilities might include:
1. Your oil pressure is actually too low. Oil pump problems are a possibility.
2. The oil pressure sensor has failed in a way that causes it to read incorrectly low
3. There is something wrong with your engine wiring harness

What does your VCDS tell you? You do have one, right?

Click to expand...

Thank you for the reply.
Unfortunately I do not have a VCDS. I know it would definitely help out lol. My best bet so far would be to ask around the local car clubs to see if anyone lives close to my area and willing to help out. Otherwise Id just have to tow it to a mechanic.

Just my perspective, but I'm not aware of any passenger vehicle with auto-shutoff on low oil pressure. Common in stationary industrial engines for sure, but would probably be a major safety hazard on something that could be crossing railway tracks or pulling out to pass.

Chances are you're seeing the oil pressure light simply because the engine has stalled on you... but the possibility that you actually have low oil pressure should probably be taken seriously first and foremost, since that's an engine killer.

It's a low oil pressure light, not a low oil level light, so you'll need a pressure gauge to check (VCDS can not read oil pressure because there's no analog pressure sensor for the ECU to see).

Then yup, you'll need diagnostic software like VCDS to scan for codes, look at how the crank sensor is working, and other common causes of a suddenly-stalling engine.

+2 on the ecu not shutting off the engine when low pressure oil light on.

If zero oil pressure happens and continue running the engine, the damage should be on turbo, cam and related parts and finally low end bearings.
Always stop as soon and safely as possible!

Thanks everyone, i managed to get it to a shop and they said its my battery and alternator....but i still think its more than that. Also this shop quoted me 550$ for a new alternator and then I asked if I can get parts my self and then they can put it in for me to which they have replied no. So I bought a new one from Rock Auto today for 200$, the same one that he quoted me 550$ for.... I have towed my car back home and going to replace it myself since i have replaced one before, now that i think about it probably 2 years ago. Hopefully that is just that and nothing else but I have a feeling there's something else going on lol

So quick question man, did you ever figure out what the problem was?

The ECU does not "detect" the low oil pressure unless RPM's go above 2k. That's when the "low oil pressure" warning shows up in the instrument panel

What is the Tach doing during the no start condition?
Any flashing Glow Plug light? Oil pressure light.

Personally, I would be looking at the G28 Crank Speed Sensor (CkSS) fault, but not at the sensor itself but rather at the harness & specifically harness chafe. Check the grounds while you are their, but I think it probably is not the problem.
http://forums.tdiclub.com/showthread.php?t=239987


Harness chafe in the MKV is now a well documented problem. Search out the subject. Good luck with it.