I've been having problems with my 98 Passat. Last winter, the oil light began flashing on cold mornings (below freezing). It only happened in the morning - I could go to work, the car would sit for 8 hours and the light would not come on later in the day when I got in to drive home, even if it was very cold outside.
Then, the oil light started coming on when I would idle for a period of time, most times this was in a drive-thru window so I began to think that maybe it involved idling with the wheel turned sharply to the left, and, oddly enough, with the drivers side window down. But I could never produce this on-demand.
Now that's it's beginning to get colder, the oil light is starting to come on each morning, even though our fall mornings are in the upper
60's.Also, when I start the car, you can hear the engine tapping for about twenty seconds.
Now, occasionally the light comes on when I'm just driving normally.
No mechanic has properly diagnosed the problem. One suggested that I had sludge, so they put some solvent in a cleaned my oil system, but this hasn't seemed to help.
Any suggestions?