Etwenty1 45 Report post Posted September 29, 2013 Looking to buy a 520i with the M50 engine for a niece, took for a drive and engine has an intermittent knock/rattle, sounds like the water pump? or front/top end of the engine. Any suggestions? 260kms. I was thinking maybe chain guides cos it is not continous, its like knock.....knock, knock..............knock. Transmission has that faint whizzing noise that follows the revs, is that terminal or a slow wear issue? Quote Share this post Link to post Share on other sites
kingkarl 136 Report post Posted September 29, 2013 The whizzing noise could be the power steering pump. If you haven't already, check the fluid Quote Share this post Link to post Share on other sites
