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2000 jetta 4cyl 5sp... water on oil filler cap! Not in oil in pan

My girlfriend recently bought my sister’s '00 vw jetta in good shape (!) 2 weeks later and, after driving halfway down the block toward college, my girlfriend came back because the low coolant light was on. The coolant was a bit low, and I thought it just had a radiator leak until we took off the oil filler cap, which was covered in beige-yellowish grease-like stuff. I assumed it was coolant in the oil = bad headgasket. We used some miracle gunk that’s supposed to cure headgaskets, and just as we finished using it (an all day affair) I realized that the oil on the dipstick was never milky looking. it looked fine. We cleaned up the filler cap, replaced with new antifreeze, etc. and my girlfriend started driving it again. she keeps a close eye on the oil and coolant and claims the coolant hasn’t gone down at all.

the car has used about 1qt of oil every 3k mi since long before this issue, but otherwise is symptomless. Never a known overheating/running hot, never white/blue smoke, only 83k miles on the clock.


It may be worthwhile to get someone with automotive experience to check the car. If the oil on the dipstick doesn’t look like a milk shake coolant is not likely getting into the crankcase. Moisture can accumulate in the crankcase and it seems to move to the highest and coolest places which are usually the oil fill cap and the top of the dip stick tube. If the thermostat is operating properly, venting is adequate, and the oil is fresh, a long drive at highway speed will usually clear up most condensation.

There likely is no relationship. The coolant could have been low, for who knows why. Watch the coolant level for a few months.

With luck the gunk you saw was just the result of condensation. Condensation is most likely to form when it is cold and the car is used for short trips. Again I would clean it off and watch it.

If you don’t observe any problems in the next couple of months, then likely there is no problem. You may never know if there ever was a problem, but if there is no additional indications, you don’t have one now. Maybe the miracle cure will work or maybe it was never needed.

Good luck to both of you.

It’s possible you sister did a lot of stop & go driving and short trips, so there will be a lot of moisture that is not driven off. and it would collect in the oil cap. About 100 miles fast drive would thoroughly “dry out” the system. This type of thing is very common in senior citizens’ acrs, including my mother-in-law. We blow out the cobwebs on the freeway every now & then.

In any case I would check out the PCV system as well.