Hi everyone!

I am new hear and I am trying to find a clue to an issue that I face with my car: Mazda CX-5 2016 2.2d AWD, 200 000km 124 000mi

It happens that sometimes when I accelerate and the engine rev is low, it downshifts and a "rattling" sound can be heard.
It can be heard before the shift or after the shift or it cannot be heard at all.

Here you can hear the sound that, in the video, souded louder than usual (when it can be heard): https://youtu.be/GfAhrDuvwjg

Thank you!

 

My guess would be detonation /pinging.

 

is detonation also valid for diesel engine? And can you tell me what does pinging mean please?

 

Pinging is another name for Detonation.

Detonation is mostly pre-ignition