I've been looking at a used 2013 320i that's in really good shape cosmetically, but when I started the engine cold I heard this rhythmic ticking from the top end that got a bit quieter as it warmed up. The seller says it's just normal injector noise, but I've read online about timing chain issues and worn lifters on the N20 engines. I don't want to buy someone else's problem, so I'd really like to have someone who knows these cars inside out take a listen before I hand over any cash. I've been trying to find Expert BMW Technicians in Abu Dhabi who can do a proper pre-purchase inspection and tell me if that ticking is a red flag or just typical for this motor. Has anyone here dealt with the N20 timing chain guide problem? Is there a way to tell without pulling the valve cover? Really appreciate any advice from owners who've been through this, I'm excited about the car but nervous about getting stuck with a major repair. Thanks.