C 220 (W205) 2018 Auto - Loud engine hum

[starlight]

My car has just been handed back after a major (B7) service (61,000 miles). The work, carried out by a trusted M-B dealer, included the latest M-B software update. I’m now hearing a loud hum at speeds north of around 40 mph, almost like a jet engine noise. It’s not unlike the sound an engine might make when an upward gear change is needed, but the auto box does move through the gears without difficulty.

I need to get back to the dealer but would like to be forearmed with any intel a forum member may be able to provide.

 

[SpikyMikey]

Have they left an air intake pipe off or unclipped?

 

[starlight]

Have they left an air intake pipe off or unclipped?

That hadn’t occurred to me. I’ll get it checked. Intuitively I reckon it has to be associated with the,software update.

 

[John N]

My car has just been handed back after a major (B7) service (61,000 miles). The work, carried out by a trusted M-B dealer, included the latest M-B software update. I’m now hearing a loud hum at speeds north of around 40 mph, almost like a jet engine noise. It’s not unlike the sound an engine might make when an upward gear change is needed, but the auto box does move through the gears without difficulty.

I need to get back to the dealer but would like to be forearmed with any intel a forum member may be able to provide.

Does your Data Card have:

CODE: 6U0 Engine sound via speaker

 

[toteimerced]

Boost leak maybe, not sure the software update is a good idea tbh.