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I did this task on Saturday, I have a few pictures and thoughts.

The hardest part about this procedure is getting the engine wire harness out of the way. I will not go into much detail there but suffice to say it is a little difficult and requires time and patience to make sure you do not break anything. Once the harness is more or less out of the way, the injector fuel rail can be easily removed and the eight bolts that hold the intake can be removed. I did not completely remove the intake manifold as there are connectors below the MAF that I found difficult to get to & in any case I had enough room to work on the front of the manifold (where the actuator is) just standing it up in the 'valley'.

I must emphasize here that it is very important to be sure you do not let any debris fall into the intake ports of the cylinder heads. I stuffed paper towels into the ports and protected the mating surfaces with clean shop towels.

In the pictures below, shown is the front of the manifold with the broken actuator in place, next is a closeup of where the break occurs, next is a comparison of the broken and replacement aftermarket part and the last picture shows the aftermarket part installed.

Be sure you order new manifold gaskets with your new part. Mine were only @ $4.50 each, cheap insurance to make sure there are no vacuum leaks once back together. It was a little tricky to get the manifold back in place with the gaskets doing it the way I did it, but do take care to make sure the gaskets do not move or slip when you place the manifold back over the head ports. There are locating pins on the mating surface of the intake manifold for the gaskets, so this helps.

Again, I cannot emphasize enough the importance of keeping debris out of the intake ports.

Reassembly went fairly quickly. Once the engine started I had a problem with cylinders 4 and 6 misfiring badly as fuel was not getting to the injectors. I have had this problem in the past when I have had to pull the fuse for the fuel pump in order to depressurize the fuel system for other repairs I have made. #4 cleared up pretty quickly but #6 took a long time to get back into the game, really had me worried for a while there... I have a feeling air pockets form in the injector rail and the affected injectors starve for fuel until the pockets disburse. Just my theory, if anyone else has an answer to this problem please chime in.

In any case the operation was a success, full power restored. :smile
 

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Bill - A very interesting post. However, some of us might be wondering (as you have not stated) -

a) What car/engine were you working on? I suspect it is a CLK 350 with engine 272.
b) What symptoms did the broken tumble flap actuator produce? Did this generate an error code?
 

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Discussion Starter #3 (Edited)
Good points!

Yes it is a M272 CLK 350 engine.

The main symptom was a very noticeable lack of power at times, especially from a stop. I have a scanner but never saw a code generated as a result of this condition. A visit to a dealership to explore options regarding the engine's balance shaft issue resulted in a stored code for the tumble flap actuator and a $1.8K estimate to replace the intake manifold to cure it (yeah right!) on top of the charge to replace the balance shaft. That is a subject for another thread as I intend to do that job as well. For the time being my wife just wanted the car to be able to get out of its own way, as it used to. ;).
 

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I realize the original post is somewhat lacking in details on doing the actual work, so if anyone is now inspired to try this themselves I am happy to answer any questions either in the thread or via PM. I really did not have time to take a lot of detailed pictures & did not really intend for this to be a step-by-step DIY thread.

I am just thrilled not to pay a dealership $1,800.00 to replace a part that can be fixed for @ $100.00.
 

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No - it's fine with your explanation. It's also great to have pictures to go with the story.

To the best of my knowledge, this is the first time this issue has been raised on this forum, so I am interested to learn a litle more adbout it here.

Any idea why the part fractured? It looks plastic. Is the replacement metal? You appear to have recovered the broken piece.

I looked up my EPC to find out what the broken piece is named, but I could not find it there. However, this WIS picture below shows it clearly.
 

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No - it's fine with your explanation. It's also great to have pictures to go with the story.

To the best of my knowledge, this is the first time this issue has been raised on this forum, so I am interested to learn a litle more adbout it here.

Any idea why the part fractured? It looks plastic. Is the replacement metal? You appear to have recovered the broken piece.

I looked up my EPC to find out what the broken piece is named, but I could not find it there. However, this WIS picture below shows it clearly.
I have no idea why the part broke & yes it is plastic. The part that broke off stayed with the long rod that attaches to the actuator, it is a ball joint. I do not have a detailed picture of the faulty part right now but the area around the ball joint that broke has some "relief" grooves around it and this may be a weak spot. I theorize that heat eventually weakened the part as I could find no real resistance in the linkage to the tumble flaps & there was no excessive carbon buildup in the manifold. I have noticed over the years that German manufacturers put plastic pieces in some of the most idiotic places and MB seems to be no exception.
The aftermarket actuator is aluminum and I do not expect any more issues.

The M273 engine has the same system and potential problem & as I have one I expect to have to do this again someday.
 

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I will be doing this on my 2009 E350 when the time comes.

keyhole, I know the OP and we can confirm his engine falls under the production of affected cars (VIN confirmed with dealer). It definitely is exhibiting the telltale signs of failure.
 

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As Andy stated above, our CLK 350 is afflicted. I was getting the 0016 & 17 codes and took it to a dealer to confirm and see how much they will compensate. I posted in one of the stickie threads about it. My wife loves the car so I will fix it.

It was while at the dealership that the tumble flap code was found.
 

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I just wanted to post one more tip about diagnosing this problem. The tumble flap levers on each side of the intake manifold can be seen if you look down the front of the manifold (Front engine cover removed). They are the black plastic pieces attached to the long metal bands from the actuator in my last picture. If you are able to easily move the levers back & forth from above, you have a broken actuator. You should not be able to move them if it is intact. I have a feeling this is how a dealer diagnoses this problem if the CEL code appears.
 

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I have a feeling this is how a dealer diagnoses this problem if the CEL code appears.
I'm sure that you are right.

However, there is bit of confusion about the two independant flap systems on the intake manifold. This ebay ad, recently posted elsewhere in the W209 form, refers to the runner flap, when it really is a part of the tumbler flap system.

Mercedes W124 204 207 211 221 Intake Manifold Air Flap Runner Repair Kit EP015 | eBay After a little research I put together the following:

Engine M272 - The Intake manifold flap systems

There are two active flap systems at work on the Intake (or inlet) manifold of this engine. It is also described as the resonance intake manifold.
The design and function of the two systems are described in the attached .pdfs, which have been taken from the 76 page training MB document covering the new features introduced with engine M272.

A. Variable length intake flap. Also named the resonance flap.
This flap, which is driven by solenoid valve Y22/6 from the ME-SFI control unit, determines whether the inlet mixture takes either the short-runner path or the long-runner path through the inlet manifold. It is an improvement on the M112 design.

B. Swirl (or tumble) flaps for left and right cylinders.
Swirl flaps for left and right cylinders can improve the mixture under specified operating conditions. Valve Y22/9 is vacuum driven from the ME-SFI control unit, and flap position sensors (B28/9, B28/10) provide feedback.
 

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The repair I have done in this thread has to do with the operation of the 'swirl flaps' in the diagram. Yes the part in the ebay ad is similar to the part I ordered and used and has nothing at all to do with the Resonance Flap.

The flap position sensors probably generate the CEL code when the actuator breaks and the tumbler or 'swirl' flaps do not move as expected as conditions warrant.
 

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Thanks Bill51sdr for your detailed information on repairing your broken actuator. Mind broke in a similar fashion which threw code P2006 for "intake manifold runner control stuck closed bank 1", so I bought a metal replacement and removed the intake manifold to install it. Oddly enough P0355 for bad crankshaft position sensor also appeared along with P2006 despite not being related at all, so naturally I also replaced the CPS and the corresponding trouble code disappeared. Thanks.
 

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Thanks Bill51sdr for your detailed information on repairing your broken actuator. Mind broke in a similar fashion which threw code P2006 for "intake manifold runner control stuck closed bank 1", so I bought a metal replacement and removed the intake manifold to install it. Oddly enough P0355 for bad crankshaft position sensor also appeared along with P2006 despite not being related at all, so naturally I also replaced the CPS and the corresponding trouble code disappeared. Thanks.
Glad it helped. I am still awaiting the day my 550 does the same thing, but so far, so good (knock on wood). After I replaced the balance shaft on the CLK 350, we sold the car to a neighbor who absolutely loves it. We actually had a bidding war as potential buyers knew of the balance shaft issue and wanted a car that would be problem free in that respect. It is still running problem free.
 

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Ah yes, speaking of which, my 350 is within the VIN range affected by the balance shaft issue. I have the settlement letter/documents but it does me no good since the problem hasn't occurred and the settlement deadline for the partial reimbursement has already past. I'm at 87k miles as of today. Perhaps I should have proactively replaced the balance shaft within the settlement period. Age-old aphorism of 'you snooze you lose' holds true, I suppose.
 

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You would not have gotten anything from the settlement unless you had a failed balance shaft and paid out of pocket to have it fixed. The settlement had such narrow terms, it was practically useless. Keep in mind yours may never fail during your ownership.
 

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. Keep in mind yours may never fail during your ownership.
'
I find that comment interesting, as with other MB 'general' mechanical faults.

Do you suspect that MB have several suppliers of engine parts, and at the start of production they all keep faithfully to the component specification. Over time, with cost-cutting etc, some suppliers depart from the original material specification (without MB knowledge) and those new problems occur.

It's the only reason I can imagine for the excessive wear only on 'some' of those sprockets.
 

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Quality Control is a problem whenever you rely on outside suppliers. When I was doing the warranty department for Max Hoffman (importer of BMW cars, just pre-BMWNA, this was about 1967 or 1968) in Hackensack NJ, we had a run of bad left door latches for the 1600-2 cars. The doors would close but not latch securely, so everyone who owned one drove around holding the driver's door shut (and screaming at me about it).

We rush emergency airfreighted a huge box of replacements, hustled them out to our dealers, and discovered that the replacement latches were no better than the original ones, they didn't hold the doors closed either. The factory then changed suppliers, and eventually the problem went away (and I could start answering the phone again).

We also had a problem with the 3,000 1800ti automatics (four door sedan) we imported. We had ALL THREE THOUSAND transmissions fail on these cars usually within a few thousand miles from new. Every one of them. We had pallets and pallets of ZF automatic transmissions in the warehouse, all dripping ATF on the floor.

Turns out the error was made by whoever did the final assembly on the transmissions. They were picking up the output shaft by the tailshaft, which allowed three tiny roller bearings in the sun-and-planet assembly to drop out of place, and the transmissions promptly failed.

It seems the sub-assembly needed to be picked up from the bottom (cradled), and not by using the output shaft as a handle. Ooopsie. We did recover a few bucks by selling the defective transmissions for scrap. BMW decided to reimburse us before we shipped them back all 3,000 dead transmissions, freight collect.

While this sounds like a huge PITA, Google "Ford Focus Getrag Transmission" and hold onto your chair.

Best Regards,

Mike/Florida
 

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Keyhole, only MBZ and their supplier (whoever that was) knows the true answer. Based on my knowledge of MBZ manufacturing processes and supplier relationships, here's my best guess. This may be totally wrong, but it's the best I have to offer:

The "balance shaft" problem is caused by its sprocket being improperly hardened so that it wears too quickly. This sprocket acts as an "idler", i.e. pivot point on the timing chain. On the M272 engine, the idler sprocket is part of and on the end of the balance shaft, which is a weighted shaft used to counteract the inherent imbalance of V6 engines. Since V8 engines are balanced and do not need such a counter weight system, the M273 simply uses a sprocket with a bearing bolted to the block as its idler.

Note that all timing chains and sprockets on all cars will eventually wear out. These are mechanical parts and with every contact of the chain, microscopic, really molecular-sized particles will wear away. Ideally the chain and it sprockets would be about equal in hardness so they wear at the same rate. And of course properly hardened parts last longer. Exactly how long they should last is up for debate, but I'd say if you over 300K miles, you got your money's worth.

We don't know exactly what happened, but some (or possibly all) of a range of these sprockets were not properly hardened. This causes them to wear very prematurely. Some failed under 30K miles. My CLK550 started showing symptoms at 27K miles. I have heard reports in the forums of some not throwing codes until 150K or more miles. So maybe all of these parts were improperly hardened, but to varying degrees. Maybe they had a flaky oven thermostat that intermittently did not maintain the proper temperatures. Maybe they had an operator who hit the pub every Thursday night and came in Friday with a killer hangover and just flubbed his job. Again we don't know. All we know is what the symptoms are (DTCs 1200 and 1208) and that there is a specific range of about the first 500,000 M272/M273 engines that MBZ knows could be affected.

So, why does MBZ not know exactly which engines will fail? Well, it's one of two things. Either these parts were not serialized, or they were, but the supplier cannot trace the problem back to specific serial numbers. Honestly, I do not think this has anything to do with "Chrysler" or cost cutting. It does have to do with the modern automobile manufacturing processes. Suppliers are used for everything. In the old days, these were all German companies that existed in fear of the Great Marque. One wrong step and they were out of business. Now, with international markets, one supplier makes parts for many cars, an d if MBZ is too annoying to work with, they just drop that line and concentrate on more profitable clients.

So, here's my theory: All the engines in the affected range of about 500,000 engines have sprockets that will fail prematurely. Some have already failed, other won't fail for a while, but none will last as long as those with properly-forged sprockets. For this reason, I generally discourage people from buying a car int he range, but if you already have one, I say just drive it as long as you can. There's no sense in wasting money on a problem that might not happen during your ownership, or before some bad driver totals your car.
 
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