JK1203 Posted November 4, 2019 Report Share Posted November 4, 2019 Hello, I have a 2002 330ci model which has about 145,000 miles on the clock. Recently it has developed a knocking noise coming from the engine. It’s loud as soon as you start the car up for 2 seconds maybe, then it quietens down as you drive it. If you’ve been driving for a while then it gets louder, and then quieter, it’s like the noise has a mind of its own. The car drives absolutely fine, no warning lights on the dash or anything else at all. Has anyone come across this before. I took it to my local garage who said that it’s terminal, completely devastated so I am trying to get it into a BMW expert. But any advice or anything would be greatly appreciated. Thank you 😊 Jessica Link to comment Share on other sites More sharing options...
McPikie Posted November 15, 2019 Report Share Posted November 15, 2019 A knock which is initially loud then quietens sounds oil/lube related. If it's constant and goes up and down with engine speed, then it's probably a bearing, so crank or little ends. Unfortunately, that's engine out job. You won't get any warning lights for this either. Link to comment Share on other sites More sharing options...
kirkynut Posted December 16, 2019 Report Share Posted December 16, 2019 Is it crank speed or cam speed? Crank speed is once per revolution of the engine and cam speed is about twice. I know how this sounds but it's tricky explaining this on t'internet! If it's cam speed it could be a dry hydraulic lifter, in which case an engine flush and a good quality 0W40 oil should make it better. Otherwise if it's con rod bearings at either end it's not good. Kirkynut Link to comment Share on other sites More sharing options...