Acceleration Buzzing Sound (CT4-V Blackwing)

[ngoni]

Yeah definitely something metallic is loose. If it was a BMW, I'd say you had a loud variable valve (VANOS) system which for many cars is pretty normal. But definitely not normal for a 4BW.

 

[Seth]

it almost seems like something internal (engine, transmission) to me. It seems directly related to RPM speed and particularly happens under load.

Things we’ve tried and ruled out are ANC (active noise cancelling) interference, and fuel pump / fuel lines.

Thank you guys for confirming I’m not crazy though. I think it’s getting louder over time, which is annoying but almost a good thing because it becomes harder for the dealership to ignore.

 

[NewCaddy]

@Seth Is sound evident, regardless of what drive/traction mode you are in?

 

[Seth]

@Seth Is sound evident, regardless of what drive/traction mode you are in?

Yep, it’s the same in tour and V and all different traction modes. I have an appointment at a different dealership this Thursday.