I've a 2008 K12S with about 38K that I bought from a dealer when it was on 21K miles.
Back then there was a noise on start up and the dealer upgraded the cam chain tensioner and the noise quit.
17K miles later I can hear similar rattling from the same side of the engine, but this time it appears when the engine is HOT.
on cold start and even the engine is warm the sound of the engine is normal but when in traffic and it heats up the rattling appears
Any experience with this problem?