the engine sounds like there is a helicopter around while inside with the windows up. It is very faint though. I wonder if it's just my car?

 

Mine has a faint ticking noise that you can hear from inside the cabin also.. I can't really hear it on the outside though.. I think it may be the direct injection but I'm not sure.. Does anyone else have the faint ticking noise inside the cabin on a c450?

 

Yes.

 

Kinda on the same topic, but what do your cars (450's) idle at once they are warmed up? Mine sits around 500RPM. Before break in, it was at about 650 or 700. Curious about others.

 

Starts around 750 and with 30 seconds drops to about 500. 960 miles, and a million smiles!

 

So is it common? (Ticking noise)

 

Mine also has a very faint ticking noise that I can hear when outside of my car. From everything I've read and heard it is normal. I'm coming up on 3k miles and I will say it gets quieter as it breaks in.

 

I can't really hear the ticking from outside... It's mostly from inside the cabin..

 

I think engine may be broken? Why is it ticking ? I can hear it in the cabin at idle!!!

 

Seems they all do.

 

Maybe shattered rings or loose wrist pins?

 

Normal sound.

 

Why is it normal? What is it?

 

So far, it is common to all c450 engines. The underlying cause is unknown to me but my salesman opined higher boost pressure.

 

But at idle there is no boost pressure?

 

Ya got me...they all do it.

 

Yeah it's normal for Mercedes V6 engines to have that ticking noise.

 

It's the direct injection. They are noisy. Just the nature of the design.

 

Don't have a C450 yet but can confirm this is nature of direct injection. It's a faint diesel like chatter at idle.

 

Spot on. There are two things that tick. Amplifier DI injectors & the slight diesel sounding combustion process & the EECS purge valve.

 

Good to know. It doesn't bother me in the least. I really, really love mine.

 

So it's not gonna explode?

 

Yes, with raw power when you drop the hammer!