'01 Jetta 2.0 oil question.....

Yeah, lower than ideal operating temps and short trips can cause that.

Remember, water is one of the biggest results from burning gasoline. Chemistry:

Hydrocarbon (HC, or Hydrogen and Carbon) combined with air (Oxygen, Nitrogen, a little Carbon Dioxide) produces Carbon Monoxide, Carbon Dioxide, Nitrogen Oxides, and lots and lots of H2O (water).

If the engine oil gets over the boiling point of water at 212F, then the water vapor will be more easily carried out the breather system into the air intake tract of the engine. Despite a popular belief, HOT oil is GOOD for the engine. Certainly do not want it too hot, but above 212F is best.

FWIW, that particular engine has that issue with moisture buildup on the oil cap pretty often. I'd not lose much sleep over it, just make sure the scan data shows the coolant getting up to temp and it should be fine.

Perform a compression test to figure out if it is one or all the cylinders and then perform a leak down test to issolate what the issue is. Both of these tools can be obtained about anywhere from Harbor Freight to Amazon for reasonable prices. I bought mine from Amazon made my OTC, I like their quality. https://www.amazon.com/OTC-5606-Com...573&sr=8-4&keywords=diesel+compression+tester

I'm not going to worry about it. The car was totalled 1-1/2yrs. ago, so it only has liability coverage. It's been a reliable car for my son so far, so I'm just gonna keep an eye on the oil level and let it roll on.Anything major and my son should upgrade a little to a truck or wagon-he's learning trim carpentry/finishing for houses and uses the car like a truck now w/tools to and from jobsite.

Wow-been awhile since an update, so here's the final one for this car. Car was still running and driving good, but the water pump started to leak a little, the oil pan plug was leaking some, as the last oil change I did the plug started ok by hand, then started going in hard, so I said eff it and just snugged it up best I could. Oil changes would be done by an extractor from now on. Both outer cv boots were torn, the passenger side almost a year, drivers side within the past couple months. Ironically, no noise or play coming from either when driving. I had to put rear pads and rotors on again, but I was able to get everything warrantied by Advance, so just my time. It passed NYS inspection on 6/13(Weds). My son had been looking at some trucks, so we went to look at some that Weds. The place where he saw an '05 Duramax, they just sold it day before. I saw one on craigslist, he called, we went to look at it, and he was sold on it. A 2005 Chevy 2500HD 4x4, Duramax, Allison, one owner, 91,500 miles, crank windows and vinyl floor,with a plow that was used for personal use only(poly blade,not steel). Really nice shape for being a NY vehicle, passenger cab corner has a hole. Guy was a city bus mechanic, had a post lift in his garage and did all maintenance himself. My son got a good deal, and is really enjoying the truck. We sold the '01 Jetta last week, it ended up with 184,200 miles, so he put almost 72k on it in less than 3 years. It was a really good car for him, he never got stranded with it, it was a pretty damn reliable car. The one thing he really likes about the Chevy is that he can go to Home Depot and get a key cut for less than $3, rather than the VW where it would be almost $250...