What's that ticking noise (Video)
 

Hi all,

My 07 350z HR recently developed a tick that can be heard inside the engine bay. From what I can tell it seems to be comming from the back of the engine (closer to the cockpit), perhaps a bit to the right side when looking from within the car. The ticking is not consistant. On cold start when the RPMs go up automatically it can't be heard. Then when they come down it still can't be heard. When I go for a drive, and the engine gets warm then the ticking can be heard on idle, but not always. I can't hear it from inside the car, even whit the windows down, but I did manage to hear it when next to a wall and the sound bounced off. While the car was warm it can be heard at idle, but only sometimes. When I was parked next to a wall and it can be heard at idle, raising the RPMs to 1000 slowed the tick, but raising it further sped it up. Anyway, really incosistent.

Here is the video of the tick after the cold start high idling has finished:

As you can see, on idle there is no tick, but comes with revs.

Here is the video of the tick after a drive, the tick here is audible on idle:

Anyone have any ideas on what the hell this could be? With my research I found that it could be valve lash due to 'lifters' being worn, it could be fuel dampers and it could also be a leak on the exhaust headers.

Also maybe a good thing to note is that the car might have a bit deeper tone than before, and the exhaust note might be a different frequency, a bit more choppy (?) - but I'm not sure if this is just my imagination because I started analysing it too much and paying too much attention to what it sounds like.

Okay I think I found it. Went for a ride and it started ticking on idle, went out of the car and took a screwdriver, started puting it on different parts of the engine and putting my ear on the top end to try to locate the ticking source. Put it on coil packs, not there, put it around a bunch of stuff and then I put it on the vapor canister purge solenoid and I can hear it clearly comming from there. If anyone wondering it's this part:
https://www.amayama.com/en/part/nissan/14930jk20a

Going to order it and hope it's an issue with the solenoid itself and not something else that caused it. Will post back once I find out.

Forgot to report back, changing the vapor canister purge solenoid fixed the issue.

Thanks for continued updates on this issue, I'm glad you found the source and cured it! I don't have an HR Z, so I don't think I have the vapor cannister, or at the least, it's not mounted under the hood, but could be part of the charcoal cannister behind the back right bumper corner. I'm surprised nobody else replied to your thread.
Cheers!
-Icer

Ah probably noone had an idea of what the issue could be, or because I answered my own question right after asking it :D