I drive a 2001 vw Jetta tdi. Yesterday on my drive home from work my oil light began to flash. I drove it home & didn’t turn it on again until this morning. The light did not come on again until about 10 minutes in to my drive. I took it directly to the place I get my oil changed (I was not due for another oil changer for 4500 miles). On my way the oil light would go off if I went above 60 mph. At the oil change facility they said my oil was overfull. They emptied & refilled it & sent me on my way saying that gas may be getting into the oil. Within a minute of leaving the light went back on & I turned around to have them look at it. They said the oil was exactly where they had filled it to (no higher). I’m taking it to my mechanic but I am just wondering if anyone has heard of this issue before or may have some insight as to what I should expect from my mechanic. It just got cold where I live so I wonder if it’s weather & sensor related.
The light doesn’t tell you about the oil level. It tells you about the oil pressure. And if the place you took it to doesn’t know what to do with this then stop going there even for oil changes - it must be a quick lube kind of place.
Do yourself a favor and stop driving the car. There is some possibility that you just have a bad pressure sensor - i.e. that your oil pressure is actually fine but the sensor is leaking or gunked or otherwise a mess. This is normally simple and cheap and harmless as long as you take care of it.
But - if you are actually having an oil pressure problem then you will destroy your engine by continuing to drive it. Someone has to put an actual pressure gauge on it & get a good read on your oil pressure.
Did you check your oil after the light came on the first time? You should never drive any vehicle that has an oil light on or flashing! Luckily your car was not empty of oil rather than overfull.
Cigroller is 100% right… Untill you get a mechanical gauge on this motor, I would not run it any more then I had to. While this is very true on any car it is ESPECIALLY true with a Turbo, it does not take much time with no oil for the Turbo to blow. Have it towed to an actual mechanic and have the oil pressure checked ASAP !!
Yup, you either have a bad sending unit erroniously telling you your oil pressure is low, or you in fact have low oil pressure. It needs to be checked to see which. If it actually is low oil pressure, it could be a bad oil pump, clogged up pick up screen, worn engine parts, or a sludged up engine.
Thanks for all of the information! It’s at the mechanic & he said similar issues as to what I’m hearing here but he’ll run diagnostics on it tomorrow. He’s supposed to be good with diesel engines but last time I had work done at the dealership they left parts off when they sent me home with it. To say the least I’m a little nervous after my last experience to have people work on it.
To be clear, you may very well have damaged your engine (and your wallet) by continuing to drive after the light came on. If this ever happens again, follow the instructions in your owner’s manual and stop immediately.
Thanks for clarifying! I drove it for about a minute after the oil light went on the first time & checked the oil level & light before completely starting it up the next morning. The engine did not sound any different than before & it came on the second time while I was on my way to the place where I get my oil changed (which is on the way to my mechanic, a 5 min drive) just to have them check it out. Alway better to assume stupid & chastise though so thanks for the belittling! 
What the OP interprets as chastisement and belittling is actually good advice on the part of lion9car.
There are several possibilities here, including, but not limited to:
A bad oil pressure sensor
A weak oil pump that is not sending sufficient oil to the bearings and other sensitive friction surfaces of the engine.
An oil pickup screen that is clogged with oil sludge, and thus is depriving the engine of lubrication
While the first possibility on the above list would not damage the engine, at this point, nobody knows for sure what the actual cause of the illuminated oil pressure warning light actually is. If you are very lucky, it will be that first item, and you will escape with a relatively low repair bill.
If you are not lucky, then it is likely to be one of the other two items, and either of those conditions could easily lead to severe engine damage within–literally–a minute or so of driving with that warning light lit up.
So–whether it relates to this car or to cars that you might have in the future, when an oil pressure warning light starts glowing, it is wise to pull over to the side of the road as soon as it is safe to do so, shut off the engine, and check the oil level. If the oil level is low, replenish it, restart the engine, and see (quickly) whether the warning light has turned off. If it has turned off, then it is safe to drive the car. If the oil level is normal, or if replenishing the oil does not turn off the oil pressure warning light–DO NOT restart the engine, and have the car towed to a qualified mechanic for examination.
A car should not be driven for more than…perhaps a minute…with the oil pressure warning light lit up, until it is determined exactly what caused the light to go on.
The OIL warning light really is a somewhat ominous signal, sofibox It indicates that catastrophic ($thousands&) damage is being done and in a few seconds the car can become a piece of scrap iron. I re-read the posts and personally don’t view any as meant to be belittling but maybe I am more thick skinned than most. What’s done is done. But on this forum we so often read posts very similar to yours and wish that all owners understood what the gauges and warning lights indicated. And really, with all the technology and bells and whistles on cars these days an audio message-IMMEDIATELY MOVE TO A SAFE LOCATION AND SHUT OFF THE ENGINE- should be part of the instrumentation package. Hopefully a glitch occurred in your car and no damage is done. Good luck.
Thank-you for the information on what might actually be wrong with the vehicle. I can understand how it must be frustrating that I & other people may seem to ignore the lights. I knew I was taking a chance but having considered what I noticed from my cars behavior & the oil level I decided to finish the drive to where I get my oil changed & then the 5 minute drive to my mechanics.
I found it to be belittling as I had just posted before his post that it was at the mechanics & he didn’t actually provide any insight as to what may be wrong with it. That was what I was originally looking for. I also noticed in many of lion9car’s previous posts he doesn’t add knowledge apart from referencing car manuals. What has been done is done I just want to understand it & know my mechanic is on the right track when I correspond with him. I’ve found issues with having my diesel engine looked at & worked on & it can be difficult to get the right answer sometimes.
Thank-you all so much for taking time to help me understand. I truly do appreciate it!
Here is a possibility, you may have a clogged or defective oil filter. You say you are not due for an oil change for 4500 miles so that tells me that you had it changed recently. That means a defective oil filter is more likely, but it could be any of the other things listed above. I just bring this up hoping your mechanic doesn’t tear down the engine without checking this first.
Put the globe on it or maybe keep it out of the wind