W202 Air Duct Whistling

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McGreggor

Active Member
Joined
Jul 6, 2004
Messages
317
Location
Uckfield
Car
CLS55 AMG
On the drivers side air-vent, I can hear a strangle whistling noise from inside the duct. It is linked to the fan, but im unsure if perhaps its a leaf in there or if the bearing has gone in the fan? I hope if right in saying there is a fan in there somewhere to the right of the steering wheel, because that is where the noise is coming from. Sounds kinda similar to when a sleave bearing fan goes in a computer, but I would think mercedes would use a better quality Ball bearing?

1998 C43 AMG
 
McGreggor said:
On the drivers side air-vent, I can hear a strangle whistling noise from inside the duct. It is linked to the fan, but im unsure if perhaps its a leaf in there or if the bearing has gone in the fan? I hope if right in saying there is a fan in there somewhere to the right of the steering wheel, because that is where the noise is coming from. Sounds kinda similar to when a sleave bearing fan goes in a computer, but I would think mercedes would use a better quality Ball bearing?

1998 C43 AMG

This time of year I'd plump for a trapped leaf mate. :confused:
 
McGreggor said:
I hope if right in saying there is a fan in there somewhere to the right of the steering wheel, because that is where the noise is coming from.
I only know of 3 fans in the cabin area, the main blower motor under the dashboard on the passenger side, the aircon sniffer in the dome light and the little cooling fan on the back of the comand unit in the dashboard, if you have one.
 
Possibly the vacuum pipe for the headlight levelling?? The one on my Vito split causing a constant whistling. Could be a possiblity
 
jimmy said:
Possibly the vacuum pipe for the headlight levelling?? The one on my Vito split causing a constant whistling. Could be a possiblity

Thats exactly the problem I have too and I think you are correct Jimmy. When I set the headlight levelling to 3 there is no whistling. If I set it at 0 then its at it loudest. Will this be expensive to rectify?

Thanks,
Steve
 
High-Lo said:
Thats exactly the problem I have too and I think you are correct Jimmy. When I set the headlight levelling to 3 there is no whistling. If I set it at 0 then its at it loudest. Will this be expensive to rectify?

Thanks,
Steve

Depends if it is the hose that has split, come undone or if it is the 'switch' that has broken. It was the same on the Vito, it was loudest on 0 and quiet on 3, trouble was the headlights lowered but would not come back up.

My solution was to sell the van, well not just because of that! :D
 
jimmy said:
Possibly the vacuum pipe for the headlight levelling?? The one on my Vito split causing a constant whistling. Could be a possiblity

Did you have the problem when the lights were off though? Perhaps it's connected to the problem I have with the drivers side headlamp, there's a motor in it thats constantly buzzing when any lights are on, but the auto leveling still works.
 
I had similar problems with my 1994 C250D. One of the pipes was loose on the left headlamp.
 
twice said:
I had similar problems with my 1994 C250D. One of the pipes was loose on the left headlamp.

The buzzing noise and the whistling air vent? I'll check this afternoon if I can find any missing pipes on the light thats buzzing...
 
The whistling noise it was; at first I thought it was comming from the front speakers or so. It stopped for a moment when I adjusted the air vent speed. I have tried to take apart the headlamp regulator switch in the cabin, but it could not be done. At last I have been checking the engine area, when I accidentally found the pipe hanging loose.
 
Ok, well I've solved the air vent whistling. Turns out the other vents were all shut off and it was just the high airflow that made it whistle! doh! :p

The front light thats buzzing turns out to be the headlight wiper motor, there was a pipe disconnected, but I'm pretty sure its the water pipe for headlight wash, made no difference anyway. The motor seems shagged, I can move the wiper by hand to the sound of grinding gears! Are these units expensive to replace? I've taken the fuse out for them to stop the annoying noise for now, but want to get it fixed asap. Gonna try to get hold of Mercman later this morning...
 

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