Rattling noise in winter
I've seen a few posts regarding rattling noise, but not sure whether they apply to CLK. In any case, I will be looking behind COMAND on the weekend, but if someone else had/has a similar problem do let me know.
Thanks!
I've looked into the issue today, but didn't manage to solve it.
Here's the problem: once I unlock the car, but before I start the engine, something behind COMAND starts making this strange rattling noise.
My suspicion was that it's something in the NAV drive in comand, but I tried it with both a disc inside and empty - the noise remains.
Problem disappears after about 10 minutes of driving, once the car heats up. So, it is something with the heater... I doubt it has anything to do with the doors since the noise clearly comes from behind the COMAND.
I've replaced water with anti-freeze just in case it was causing problems.
Anyway, can lkchris or anyone else give me a few hints/links that might give me some further suggestions on what to try? (I'm a newbie to cars in general and MB in particular).
https://mbworld.org/forums/showthrea...t=heater+noise
But my noise is different, and what's important i can hear it before starting the engine. My noise is kind of rattling, as if a small piece of plastic has come off... but the noise disappears, which suggests that everything inside is alright... :?

Edited: this car still appears to have vacuum controlled flaps, should not be the above issue then.
Do you mean you only open the door, or do you also switch ignition on?
I'm not sure if the small interior temp sensor fan would start before ignition is switched on, I don't think so.
Last edited by Diesel Benz; Dec 16, 2007 at 12:40 PM.


Anyway, I put in a whole bottle of anti-freeze now so there isn't much water but the noise persists... so, I guess it's something else.
I've been reading other threads and there was an old (2004) post with some similar problems... I now also hear whistling noise when turning heater in the morning. Those threads don't post any solutions, so it's probably 'normal'... as in, tech people don't consider it significant enough to solve..
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Anyway, I put in a whole bottle of anti-freeze now so there isn't much water but the noise persists... so, I guess it's something else.
I've been reading other threads and there was an old (2004) post with some similar problems... I now also hear whistling noise when turning heater in the morning. Those threads don't post any solutions, so it's probably 'normal'... as in, tech people don't consider it significant enough to solve..
A frozen washer pipe could make some noise but those are all at the engine bay or the hood and the sound should not appear inside.
Did you already try to take the Comand unit out? Perhaps the source would come more obvious. Comand should have a cooling fan, gyros and the CD(/DVD) drive, did you have a disc in the unit?
I wish you luck with the fix and hope the temp reading was an error, not that nice to work in the car if it is really cold.
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But I doubt an MB would be driven at that place.

I've looked into the issue today, but didn't manage to solve it.
Here's the problem: once I unlock the car, but before I start the engine, something behind COMAND starts making this strange rattling noise.
My suspicion was that it's something in the NAV drive in comand, but I tried it with both a disc inside and empty - the noise remains.
Problem disappears after about 10 minutes of driving, once the car heats up. So, it is something with the heater... I doubt it has anything to do with the doors since the noise clearly comes from behind the COMAND.
I've replaced water with anti-freeze just in case it was causing problems.
Anyway, can lkchris or anyone else give me a few hints/links that might give me some further suggestions on what to try? (I'm a newbie to cars in general and MB in particular).
Grane
Yes, it does get that cold in Russia and CLK is really not the best choice for this kind of climate. In the mornings it takes about 10-15 minutes to warm up the car and what I find somewhat alarming the displays change very slowly when the car is cold (I mean the displays behind the wheel. Comand works fine.) Once the car heats up both the noise goes away and display works slowly.
And as for Grane's comment, that probably is the solution to my situation.. except I bought the car used (in Germany) and doubt I will get warranty honored here. Usually, we're charged for just about anything
Yes, it does get that cold in Russia and CLK is really not the best choice for this kind of climate. In the mornings it takes about 10-15 minutes to warm up the car and what I find somewhat alarming the displays change very slowly when the car is cold (I mean the displays behind the wheel. Comand works fine.) Once the car heats up both the noise goes away and display works slowly.
And as for Grane's comment, that probably is the solution to my situation.. except I bought the car used (in Germany) and doubt I will get warranty honored here. Usually, we're charged for just about anything

i've seen cars when under cold temp, the windshield rattles before the car was warmed up.

I've looked into the issue today, but didn't manage to solve it.
Here's the problem: once I unlock the car, but before I start the engine, something behind COMAND starts making this strange rattling noise.
My suspicion was that it's something in the NAV drive in comand, but I tried it with both a disc inside and empty - the noise remains.
Problem disappears after about 10 minutes of driving, once the car heats up. So, it is something with the heater... I doubt it has anything to do with the doors since the noise clearly comes from behind the COMAND.
I've replaced water with anti-freeze just in case it was causing problems.
Anyway, can lkchris or anyone else give me a few hints/links that might give me some further suggestions on what to try? (I'm a newbie to cars in general and MB in particular).
Good luck,
Grane
On a related note, there are contradicting claims on the net regarding warming up cars in winter (that is letting the engine work for a while, before taking off). Now, in my official Toyota handbook it was written that it is NOT recommended to 'warm up' the engine, but rather begin driving slowly.
I wasn't able to find a similar note in MB handbook, so can some experienced user tell me: under such temperature extremes am I damaging the engine by letting it run for about 10 minutes before taking off?

On a related note, there are contradicting claims on the net regarding warming up cars in winter (that is letting the engine work for a while, before taking off). Now, in my official Toyota handbook it was written that it is NOT recommended to 'warm up' the engine, but rather begin driving slowly.
I wasn't able to find a similar note in MB handbook, so can some experienced user tell me: under such temperature extremes am I damaging the engine by letting it run for about 10 minutes before taking off?
The problem with idling only is that the engine would generate very little heat with no load and there is a lot of water in exhaust gas that starts condensing and remains in the engine, spoils the oil and then lubrication stops working...
I would certainly use a block heater or a fuel heater to warm up the engine a bit first (say to 0 Celsius or above). Still you would have to drive carefully first as the tranny and the suspension and everything else is cold.
It would be important to run sufficiently long with a fully warmed up car at least frequently if not every time.








