Using Oil?

[OldAudiA4]

AEB Engine, 150,000km, 10,000km since last oil change. I park on a slight slope at night and noticed a clacking noise upon starting which would disappear after a few seconds. I checked the oil and it was reading empty. I put about 2 litres in and it's slightly overfull. A few days later, I checked it again and it was reading empty. Put another 2L in it and it's showing just above full for now. No visible oil leaks around the engine bay or under the engine and it's not dripping oil. Exhaust looks ok. Coolant looks ok. Any ideas?

[redline380]

2 liters in a couple days would produce a decent amount of smoke.

[Tanzimur]

are you checking on level ground and when the engines cold?

[OldAudiA4]

are you checking on level ground and when the engines cold?

Level when warm.

[Bordom]

You're leaking. Check the intercooler piping

Everything graciously mispelled by Android

[OldAudiA4]

So it was a leaking oil filter. When I took it into Audi prior, the oil filter had been removed to replace a gasket and then the oil filter was put back on. It had scratches on it and looked like it was cosmetically damaged from taking it off and putting in on. Approx 12 months later, developed a significant leak. I first noticed it by when I started the engine on a slight slope, a clacking noise was evident for a few seconds. The oil temp never went above the normal spot. I'm just wondering if any damage could've been done to the engine while I was running with the oil leak from the filter. Also, the oil pressure warning light never came on while driving.