I did a search prior to posting, maybe I have used wrong search terms…

What is this noise? Apologies, not yet savvy on how to embed.


Last edited by sebastian_n7 on 25th Feb 2023 2:03 pm. Edited 1 time in total

I don't know the link doesn't work  2009 FL2 S now gone
2011 FL2 HSE AUTO
2012 FL2 XS AUTO
2000 Kawasaki er 5

I can hear the valve train is noisy.
There's a hollow clacking sound along with the valve train clatter, which could be anything. It's a regular noise though, which suggests it's something synchronised to the crankshaft, so it could be timing belt related. It actually sounds like a rod bearing has excessive clearance, but that's unlikely unless it's due to a bearing defect. Hyundai Ioniq 5 Ultimate. The family car.
2009 Rimini Red SE TD4. Gone.
2006 Tonga Green i6 HSE. Gone.
Audi A5 convertible, my daily driver.
1972 Hillman Avenger GT, the project.

Forgot to mention, the odd sounding metallic chirp/clack only comes on on two conditions: cold engine startup with aircon is on. I tested the hypothesis with aircon off. My first thought was a/c or alternator freewheel/clutch or a tensioner… that would eb the quick solution.

If it always correlates with AC on, that's a strong case for AC compressor. Possible it could be the AC clutch, and it only makes noise when under load.

Less likely but slightly possible that it's something else on the belt (idler, tensioner) and only makes noise with AC load.

But pretty much 100% that it's something on the belt. Which is a lot better than valvetrain or bottom end.

Thank you for the suggestions, will go ahead and source a/c clutch replacement.

Update. Turned out to be alternator pulley, sourced a recon unit. All good!