Hi Kcahill,
I have a 2007 CLK350 which had similar manifold issues. I replaced (DIY) the whole manifold with the Pierburg part and all manifold-related issues were resolved (2 years on, now 100,000k total). My understanding is that as soon as the load conditions drop past the predetermined vacuum and rev parameters the intake will revert immediately to "short" runner state. BTW (maybe a silly question) but did you erase the DTCs via your code reader and confirm they were gone after your "fix"? (otherwise it can take several engine start/stop cycles to be automatically be removed).

 

 

What happens is that oil residue sucked into the manifold via the PCV system creates sludge that interferes with the movement of the flaps. This is what causes the actuators to break or for them not to return to their resting state. Replacing the manifold is the best solution.

 

This video shows that cleaning the inside of the manifold may be required due to the build-up of oil gunk and carbon.

On a second note, I got the infamous P2006.
So, I need to replace the tumble flaps lever that broke at the ball connecting the diaphragm plastic rod. Could you share where you got the metal lever?

Finally, is everyone absolutely sure there is no way I can do this without the intake manifold from the car? What if I remove the auxiliary air pump and whatever is around it?

 

This video shows that cleaning the inside of the manifold may be required due to the build-up of oil gunk and carbon.

On a second note, I got the infamous P2006.
So, I need to replace the tumble flaps lever that broke at the ball connecting the diaphragm plastic rod. Could you share where you got the metal lever?


Finally, is everyone absolutely sure there is no way I can do this without the intake manifold from the car? What if I remove the auxiliary air pump and whatever is around it?

I bought the lever from eBay , cost 25AU dollars. Made of aluminium .
There’s a few for sale , worked pretty good .

 

When I did the lever replacement on the ML350, there now way to do it without removing the manifold because the engine block lift ring was in the way. Even if that had not been the case, the kit I bought required some drilling and replacing plastic pins with bolts, ant there is now that could have been done with the manifold on the engine. Honestly, removing the manifold is not that big of a job, just get a new gasket.

Oh, and it may be a good idea to clean the inside of the manifold because that buildup is likely the cause of the lever breaking.

 

So I changed the manifold with a brand new one.
solved all problems no DTCs showing.

interesting thing was the existing manifold appeared to be fine , I looked inside after I removed the throttle body . It appeared to be clean, no build up really.tumble flaps seemed to be intact no signs of degradation.

But the rubber vacuum hoses were all a bit worn .
either way , nothing like having the new part anyway . Don’t have to worry about that one for a while .

for anyone who is changing theirs the torque settings for the manifold bolts is 9Nm as it’s made of magnesium .

I also don’t think it’s possible to change the tumble flap laver cam by just removing the secondary air pump,
You can change it without pulling the entire manifold out if you lift the front of it up .
Also fuel rail doesn’t need to be removed either.

 

So I changed the manifold with a brand new one.
solved all problems no DTCs showing.

interesting thing was the existing manifold appeared to be fine , I looked inside after I removed the throttle body . It appeared to be clean, no build up really.tumble flaps seemed to be intact no signs of degradation.

Interesting. Did you actually open it, or just look through the ports? I once saw one opened at it was VERY sludgy.

I also don’t think it’s possible to change the tumble flap laver cam by just removing the secondary air pump,
You can change it without pulling the entire manifold out if you lift the front of it up .
Also fuel rail doesn’t need to be removed either.

The problem is that most of the lever kits require some drilling, and you don't want to do that over the open intake ports. Once you get to where you can lift the manifold up like that, the few bits you'd need to get out of the way for full removal are minor. Yes, you would need to disconnect and unbolt the fuel rail, but by lifting it, you've already pulled it out of the injectors. I have just learned that sometimes, trying to save a few minutes of wrenching costs me more frustration later in the job.

Glad you got it fixed!

 

I had this problem some years ago. I swapped out the intake manifold for a new one. It’s also recommended to change the oil separator and PCV cover because this is what causes the tumble flap arm to break in the first place. Bad separator allows oil to get into the manifold and it gets gunked up and puts stress in the arms causing them to snap. You don’t want to have the same issue with a new manifold but not treating the cause of the problem at the same time.

 

 

Oil separator and cover is an easy job. I added a video of that particular repair

 

Hi all,
I am going to change the oil separator pan and cover (passenger side), and the oil breather (driver side). Thanks for the heads up. However that is now the least of my worries.

I took the manifold out and the lever is indeed broken at the ball joint with the center diafragm. I'm not planning on putting a new manifold. Instead, I cleaned it up to almost new condition. I was not planning on opening it up. Unfortunately, I discovered that while all arms and flaps are intact (and really solidly built), the bushings are broken. What I'm talking about are small plastic pieces that are used along each of the runner flaps' arms to help the arm rotate without wobbling. There are 13 of them. Six on the driver side, and 7 on the passenger side. All the ones on the driver's side are broken but were still functioning, except for one that had a piece missing, most probably while washing it. All the broken bushings were a catastrophe waiting to happen. They are not hard plastic, but they sure can damage the valves or pistons if sucked inside the cylinder.

I'm going to buy the repair kit with those little seats to rebuild my manifold. I have more time to spare than pay $650 on the A2721402401 manifold (FCP Euro price).
I found them on walmart.com (https://www.walmart.com/ip/For-Merc...etal-Flap-RK5691M-Air-Intake-Manifold-Repair-Kit-05-06-07-08-09-10-11/836349788)

I'm attaching pictures here to show you what I mean.

 

Hi all,
I am going to change the oil separator pan and cover (passenger side), and the oil breather (driver side). Thanks for the heads up. However that is now the least of my worries.

I took the manifold out and the lever is indeed broken at the ball joint with the center diafragm. I'm not planning on putting a new manifold. Instead, I cleaned it up to almost new condition. I was not planning on opening it up. Unfortunately, I discovered that while all arms and flaps are intact (and really solidly built), the bushings are broken. What I'm talking about are small plastic pieces that are used along each of the runner flaps' arms to help the arm rotate without wobbling. There are 13 of them. Six on the driver side, and 7 on the passenger side. All the ones on the driver's side are broken but were still functioning, except for one that had a piece missing, most probably while washing it. All the broken bushings were a catastrophe waiting to happen. They are not hard plastic, but they sure can damage the valves or pistons if sucked inside the cylinder.

I'm going to buy the repair kit with those little seats to rebuild my manifold. I have more time to spare than pay $650 on the A2721402401 manifold (FCP Euro price).
I found them on walmart.com (Robot or human?)

I'm attaching pictures here to show you what I mean.

I am rebuilding an intake manifold on my wife's 2009 e350 4matic. I bought some aluminum parts and rebuild kit for the entire intake. The one thing I am unsure about is what type of sealant to use to reassemble the interior intake upper and lower parts . Anyone who has done this job knows what I am talking about. Not the 2 main pieces together...I have the OEM Mercedes black sealant for that. I would just use that but the 2 intake manifolds I have disassembled for parts had a gray colored sealant...not black.
I am literally sitting here trying to find the appropriate sealant as I am about to reassemble everything.
Thanks for taking the time to respond.