S52 Engine Ticking On Rev http://www.youtube.com/watch?v=IgupecXbeVE At Idle http://www.youtube.com/watch?v=4chjjv7WkOw I purchased my 1999 M3 about a month ago. During the 2 weeks I drove it, I noticed a really loud raspy hammer on metal sound coming from my engine. I emailed the previous owner who said it was the oil being too thin. I changed the oil (15w50 and a quart of 0w-40), to no success. I took it to a BMW performance shop who said it was definitely bad lifters. When pulled, the lifters were pitted and squishy. They had a machine shop check them who confirmed they were bad. Lifters replaced, engine buttoned up, noise was a lot quieter, but still could hear it, especially at cold start. For 10-15 seconds the noise would be loud and then get quieter by about 30%. (This is what the shop has told me since they have had the car for the past 2 weeks). I was told that the last of the ticking could be coming from a faulty lifter carrier, not keeping the oil centralized around the lifter. I was also told that it could also be oil viscosity, air in the lines still, or a gasket that's allowing air into the system. Oil pressure is good. The shop is currently researching it to its full extent, but I wanted to do my own investigation to help them along as much as I can. Any suggestions/help/whims would be much appreciated!