Guys hello! Have a strange problem I'm hoping someone here has encountered before. My girl's 2006 G35 5AT Base Sedan (135k miles) has developed a weird intermittent "cluck" that gets louder and more consistent as the car's warmed up and driven. Here's a video with the sound :

[youtube]https://youtu.be/XDNb-SETbpA[/youtube]

I stuck a stethoscope around the engine and the sound's loudest on the upper passenger side of the timing cover and also at the same time at the power steering pump. I can also feel a slight accompanying thump through the stethoscope.

The car rattles sometimes upon cold start and consumes oil, could it be related to timing components? Given the the sound isn't a consistent clucking/rattling, could it be a loose tensioner or chain guide getting occasionally rattled? It drives great otherwise even though it's been flogged pretty hard for most of its life.

Any and all insight is very much appreciated, THANKS GUYS!

It was the alternator. Hope this helps someone with a similar problem down the road.