spchaser

I've had this ticking noise in the cokpit (funny the forum won't let me spell ****pit) of my 01 c320 that is loudest at 20-40 mph. The frequency slows when the car is at slower speeds and gets faster at higher speeds. It sounds too fast to be hitting once per revolution of the tire. It is not there when the car is cold...but after prolonged driving at freeway speedsit starts up. It is not terribly loud, but noticeable. If you open the windows, you cannot hear it.

I have replaced all four tires because of this sound...and it persists.

I have had 2 engine techs look at it...without identifying it. One had suggested that it might be the odometer- which i doubt

Most recently I have taken it to fletcher jones who replaced the purge valves...but it still persists.

what could it be?? I've searched the forums and from what has been posted, i'm not so sure it is the purge valves.

yodlebenz

i have the same problem. just developed in the last couple of months. i just had tires rotated and still have noise. i've removed anything that might rattle. no luck. still havent dropped it off for service... grrrr. drives me crazy.

how many miles do you have on it?

spchaser

25k+


If you drop it off, make sure the noise is present when you do. Mine is intermittent and cannot be properly diagnosed unless they hear it.

kusumoto

Hi there,

Mine had the same problem developed last summer and was fixed.

Seems it is a common problem to W203 because some time after my complaint the dealer phoned me telling a new part was introduced.
The problem was;
Insulator inside the propeller shaft tunnel (From the cabin, it is outside?) tended to come off the wall.
When the tunnel got hot, the insulator off the wall hit the propeller shaft.
So I could hear the sound on sunny days about after 30 minutes driving at the rate of tire rotations. And the sound I could locate coming from the rear seat air-con outlet.

I did not see the part personally, don't know about the number, but it is said to be a bracket or cramp to fix the insulator to the wall. Before this new part, the dealer was suggesting to cut the part of the insulator.

So good luck to you at your dealer.

spchaser

yes...your description sounds right. It is especially worse on a sunny day. I can also best localize the sound somewhere in the center console... The car is at the dealer right now at this moment. Maybe i'll mention it to them.

the stupid thing was that when I took it to the dealer, after 50 minutes of freeway driving, the noise wasn't there!

Thanks for your reply.