Uhm, don't know quite how to tell you this nicely, but ......... I think you are in way over your head regarding problem 1.

There is no air intake under your seat (unless you want to recirculate farts). The two openings you see underneath the front seats, are the foot vents for the rear passengers. The recirculate function is electronically disabled after a specific amount of time and fresh air pulled in from the outside. It is part of the design since MB presumably thought it would be bad for their image if the occupants of their cars die due to lack of oxygen.

So for your own safety and to enjoy proper aiconditioning, unblock the external intake vent immediately. Then, read the stickies on how to replace both the normal cabin filter (for air flow volume) and the carbon filter (for removing bad smells). Once you have replaced the filters with good quality filters, especially the carbon filter, drive the car and enjoy the cool, non-smelling air the way the engineers designed it. :surrender:

 

Kobus, thanks for correcting me. I just assumed those vents are drawing in air.

But I don't think the air filters are clogging the air output from the aircon vents. This is because, when I lift up the outside air intake flap (from engine bonnet), you can see alot of vacuum was created and the air rushed in and the cabin's aircon vents will have very high volume of air.

Unless outside air intake bypasses the filter you mentioned?

Please advise.

 

No, all outside air goes through the filters. If you think the outside vent is not opening sufficiently, try and determine the reason for that. I think it is controlled by vacuum, so check your vacuum hoses. In the worst case, the piston controlling the flap may be bad, but I've never heard of that happening.

 

Kobus, the outside vent's opening/closing action is controlled by a rod that goes deep inside (I thought it was a motor). I can get some photos tonight when I get home just in case we are referring to different parts. This motor, seems to be faulty because when I pressed the Recirculate button (LED light comes on), you can see the flap trying to close but it's very weak and gives up without completely closing. When I pressed the Recirculate button again (LED off), the flap opens a bit more. Essentially the flap is now opened whether or not recirculate is On or Off. This is why I kept on smelling fumes now.

 

If your air conditioner uses a LCD display and not the rotary controls, you can use the inbuilt diagnostics to run a flap test. Check the stickies for information on how to do the test. If your aircon has rotary dials, you're out of luck for the test.

 

yeah mine's a rotary dial. In fact, I run through all the threads and many were talking about the diag tests and I was disappointed that mine didn't come with it.

Btw, where are the vacuum hoses for the recirculate function? The rod holding the outside vent, seems to be going behind the blower.

From the engine bonnet, when I opened up the outside air vents revealling the flap, I can actually see the blower from there.

Btw, I was thinking of modifying my rotary dials to the LCD control but then again I was thinking this might complicates things in future especially since more electronic could mean more problems. And also this mod will require changing of the wood panel.

 

Ok I managed to find some photos online showing the engine bonnet, and I've circled the location where I was referring to the intake flap.

Let me know if this clarifies. Thanks.

 

Done some researching on "w210 recirculate vacuum actuators" and it seems like it's really operated by vacuum. Not sure if I am able to trace where the leak was. I honestly couldn't find much discussion on this topic. Maybe not really a common problem?

I'll be taking out the glovebox to have a look. thats where I think the rod controlling the flap is going towards. Currently in the cabin, when I pressed the recirculate button, I no longer hear any sound. Previously when I pressed the recirculate button I could at least hear "whooop!" and I believe the flap was closed.

 

I've uploaded the photos showing the exact flap I was referring to. This is on the left hand side of my car as mine's a LHD.

I realized that the outer flap controls the outside air intake. The rod that holds on to the flap....I traced it and it's actually connected to another internal flap. This internal flap is the one controlling whether or not air is drawn in from the cabin (circulating).

The internal flap seems to be moving on it's own and when it moves, it pushes the rod to open/close the external flap for outside air intake.

After fiddling around I don't think the problem is due to vacuum. This is because if I stick my hand through the external flap, I can manually open the internal flap. But when I turn off recirculate, sometimes the internal flap closes. If it's a vacuum problem, I would assume it wouldn't open / close and not just 1 way.

Any advise would be appreciated.

 

No air filter in sight. Someone's been in there.

Is there even a linkage in place?

 

Air filter? Isn't it behind the glove box? I didn't take it out again today and not too keen as I found 1 of the screws a bit damaged (plastic). I don't think even if I take out the glove box I could see the internal flap. I believe (not sure) that this internal flap thing could be connected to the whole assembly (again I'm assuming).

I've been trying quite hard to find the breakout drawin assembly of this aircon vents but haven't got success.

What linkage? Yes I took out the linkage (rod). With the linkage in place, it links the internal flap with the external flap. If the internal flap closes, it will open the external flap. And vice versa.

 

The last time I got the aircon serviced, I remembered the carbon filter was broken and removed. That was below the blower right?

Are the airfilters supposed to be ontop of the blower? The view of the camera was from the engine bonnet.

 

The dust filters are on top, before the fan intake, access is behind the glove box. The carbon filters are located in the air plenum to the left and after the fan. Both very easy to change!!

PS: Anything new at the Hawkers Market!!

 

Dust filters on top before the fan intake? Oh dear...I don't know why it's missing.

I found an air filter at the bottom of the glove box instead. thats the only airfilter that I could remember and it looks very dusty. Could my model be only having this filter? It looks different from the photos I saw here...location of the airfilter was different as well. Perhaps my LHD W210 has a different aircon?

What could be new at the Hawker? These are all going to be closed by the govt one after another you know

 

Btw guys I've fixed the problem after spending 1/2 day on it. Could have be quarter of the time if it was done by a professional.

The problem was due to the vacuum actuator which was leaking. I opened the glove box, found the internal flap which had a vacuum actuator connected to the flap, controlling it opening/closing. When I press the recirculate, the internal flap was supposed to be opened - vacuum actuator will turn the flap as vacuum will come into the actuator.

When you turn off the recirculate or if you turn off the aircon/car, what happens is that the vacuum will be lost and the actuator will turn the flap closed. This is because the actuator had a spring inside pushing it backwards.

What I did was, since there was a hole in the rubber of the actuator, I removed the spring so that it will not spring back and close the internal flap (I needed the internal flap to be opened always since I want the external flap closed).

This was the solution and the photos are below. Hopefully this will help someone someday.

 

Btw I could have fixed the actuator as well. It cost $55 for this actuator but it's not really about the money....if I have fixed the actuator, then the default would be "outside air" and if you press the recirculate, then only you will close the flap to keep the fumes out.

In where I stay, our car travels are always very short (30mins-1hr) and so it's impossible for us to deplete the amount of oxygen in the car.

I did a check at the aircon workshops here and found that infact, permanently closing the external air flap is a common mod they do here. we've got too much traffic, polluted air.....breathing in circulated air is definitely healthier.

 

Btw, this is how it looks like behind the glove box. I couldn't find any filters here?

 

The W210 are just reaching the age when the vacuum elements are giving up, so that would be my candidate for stickies.
The topic is well covered in W124, where the elements operate in similar way, although controls are different.
You might say that $55 for new element is not much, but consider the car is having about 10 of them and once one fails, the other will follow.
There is a supplier for diaphragms only, what comes to less than $10, but not all models are available. At this point I would direct you to W124 forum and hopefully we can find cheaper parts for W210

 

10 of them?? oooh...I know the door locks of W210 are operated by vacuum. What else is vacuum? I heard from the parts shop that there's 2 other vacuum elements for the aircon but something I didn't managed to find.

[edit: oh yes they are called elements, not sure why I kept saying actuators - must be what I found on google]