Replace the battery

Telcoman

 

The video was kind of short, but I didn't see your RPM needle move when you were cranking. Does it move when you crank the engine? It could be your crank sensor if that's the case (not a full proof test though).

Try spraying some brake/carb cleaner or starting fluid in the intake close to the throttle body. If it starts then you have a fuel delivery issue if still doesn't you want to see if you have spark. If you don't have spark then I'd look at your cam/crank sensors too (as long as the wiring looks good).

Check your battery voltage with a multimeter (~12.6 I think you are looking for) and try tapping the starter with a mallet or something while someone cranks. That noise when you were cranking didn't sound normal to me (so, it could be your starter).

 

Kinda sounds like the starter is spinning but not engaging. Is your engine even cranking?

 

That's what I thought too and I couldn't really tell from the video. That's what happened with my starter though the bendix starting flopping around and occasionally it would catch and start the car up. Luckily, it's an easy swap on the G35; I think on the later models it's an all day event.