Mattsuzie: That little "tin foily" thing COULD be a problem. About 4 years ago, on my wife's Jetta Diesel - one of the "tin foily" seals from a litre of oil accidentally fell into the engine while adding oil. For 2 weeks nothing happened. Then my wife called me at work and told me that every time she stepped on the gas and the revs hit about 1800 RPM the low oil pressure light started blinking and the buzzer sounded mercilessly. Taking her foot of the gas - the light would go away and the buzzer would stop. I thought it was strange as low oil pressure usually occurs at low RPM not high. I told her to shut the car off and drove to where she was. When I started the car - it was exactly like she said. It did not make sense - revving the engine produced lower oil pressure - lower revs produced higher oil pressure. I towed the car home and pulled the oil pan - that stupid round "tin foily" thing had made it into the oil sump and had gotten sucked up against the screen for the pick up to the oil pump - effectively plugging about half the intake of the screen. So at low RPM there was sufficient oil to give the required pressure but as you revved the engine the reduced oil flow caused reduced oil pressure by oil starvation- setting off the alarms. Removing the stupid "tin foily" thing and a new oil pan gasket and the car is still rinning great to this day. Needless to say I am very careful with those "tin foily" things now. I would strongly suggest that you keep an eye on your oil pressure if you leave it in there - may not happen today or tomorrow - BUT BEWARE!!!!
Morris