C300 engine noise
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Maybe this is normal for mercedes engines?
I know for a fact it's not for other manufacturer engines.
I hope that's normal too...
Last edited by narky; Jun 17, 2008 at 03:42 PM.
Ours continues to be the best car we've owned, and I've had 50+ cars since 1962. Idle smoothness can't be compared to a straight 6, but I have no complaints about the way it behaves.
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If you start up in a "hard walled" (brick or concrete) garage you get all sorts of reverberation noises. I park in an underground garage at work and all three of the last cars I owned made weird noises as I went down the ramps, close to concrete walls.
If it is something else take to the dealer.
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, you may want to change dealership or get the service manager to look into it if the advisor is not helping you . it is not normal to have that kind of noise during start up
On another note, does anybody know if this car has a compass. It has P1. No MM package.
One thing continues to rise to the top with this car. It's intuitive. Seems like whenever we reach for something, it's there. Except for the turn signal.
to the post up top, yes the P1 pkge does have a compass, you just have to mess with the stearing wheel buttons to get it to show.
I won't go further until I hear more.
-Ryan
I am not having much luck finding the compass. Does anybody have any more info on where to find this in the menus. RTFM is no help.
Thanks
Ah ha. My C300 started doing this at about 4000 miles (now 5700) and my '01 C320 (M112 engine) did the same thing from about 1000 miles up until 65000 miles when I traded it.
It is the sound you usually hear after an oil change (by you) when the oil pump has drained and before it primes itself and you normally don't hear until the next oil change. If we DID have an oil pressure gauge, we would hear it go away as pressure comes up. But, my C320 did this 90% of the time when starting, hot or cold. And it never increased or decreased in volume.
There is a check valve on the output of the oil pump (I looked at the parts microfiche showing the pump) to prevent drainback after shutdown and I think my C320's was stuck open, so it took a few seconds to pressurize the system again.
Since I had never heard it until recently, I thought that I wouldn't hear THAT noise again, but here we go again.
I intend to discuss this with the MB service manager with a thought to replacing that check valve under warranty.
BTW, it's a rod knock and based on the 65K miles in the C320, I guess it's harmless, but annoying.
Last edited by RLE; Jun 22, 2008 at 11:53 PM.
Maybe this is normal for mercedes engines?
I know for a fact it's not for other manufacturer engines.Most DOHC, multi-valve engines do this, some are noticeable some are not. Without hearing the sound we're all guessing here. Mercedes engines do tend to sound kinda gruff at time upon startup. It could be bad gas, or a number of things. You should let the dealer keep it overnight if it really bothers you that much.
M
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I did bring it up with the dealer though. Answer: normal operation.
Doesn't really bother me, it's a lease and I only drive it to-from work now ... and if I have to wait for a tow on the way to work, I won't be heart broken ... just adding to the thread that mine sounds thrashy and "diesel-y" when it first starts.
But I'm also pretty sure I just have a cursed car anyway.
Last edited by Les-10; Jul 5, 2008 at 11:53 AM.
The sound only lasts for 2-5 seconds and sounds like bearings or a rattling sound.


