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2007 E320 Bluetec
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Recent M55 shutoff motor replacement

I recently experienced the power loss symptoms on my 2007 E320 Bluetec many of you described. On the third trip with the symptoms the check engine light came on. No longer inclined to tinker, and also because I was on a road trip, I had the nearest MB Service Center make repairs. They charged 5.5 hours plus parts, a total of $1,200, which, from what I have read in this thread, is not unreasonable. Particularly since the car has driven like is should since, with lots of that lovely diesel torque.

I did wonder what happened, where the M55 motor is and what it's purpose is. I wanted to thank all earlier contributors to this thread for allowing me to find answers to these questions in what you have written in the past.
 

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GL320 CDI - 2008, '04 Touareg V10 TDI, '85 Unimog U1700, '83 Mitsubishi 4WD turbodiesel PU
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On the OM642 motor on the GL (and I doubt that is your motor designation on the '07 E320 Blutec) the M55 motor is a servomotor that operates a set of butterfly valves, one valve in each intake port in the intake manifold. The OM642 is NOT a Blutec motor, at least in 2007-8 GLs.
 

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2007 E320 Bluetec
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Thank you FourDiesel for your comment. I'm a Newbie to this Forum and thought it quite likely that I'd mistakenly applied the experiences related in this thread on the 2007 GL320 to my 2007 E320 Bluetec. However my User's Manual Technical Data section states my engine as an OM642 - same as in the 2007 GL320. (Perhaps relevant here is that my car does NOT have the urea injection system).

At any rate I think I can still apply to my '07 E320 Bluetec what has been stated in this thread about the M55 shutoff valve motor on the '07 GL 320.

Can you recommend a publicly available three dimensional diagram for the OM642 engine with cutaways that will allow me to better understand the location and looks of this infamous motor and the valves it actuates?
 

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GL320 CDI - 2008, '04 Touareg V10 TDI, '85 Unimog U1700, '83 Mitsubishi 4WD turbodiesel PU
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I'm a little confused since I understood that ALL BluTec engines use Diesel Exhaust Fluid (DEF). If yours doesn't use DEF then it probably really is a OM624 diesel. In any event, someone, (not me) posted a bunch of pictures recently showing what they had to take off/apart to get at the motor. Use the search to see if you can find it.
 

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2007 Mercedes 320 Bluetec
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I've been experiencing this problem with my 2007 E320 Bluetec (yes, Bluetec, OM642, no Adblue). From the Star Service DVD, here's a description of the function of those pesky flaps and the M55 motor:

Intake Port Shutoff

The intake manifold contains two intake ports for each cylinder:
* Charge intake port (with flap)
* Swirl intake port

The charge intake ports can be closed by means of flaps. They are held in the open position by spring force. The position of the flaps is determined according to the performance map stored in the CDI control module. The CDI control module reads signals from the following components:

* Mass air flow sensor
* Charge pressure sensor
* Charge air temperature sensor
* Pressure sensor downstream of air filter
* Accelerator pedal sensor
* Crankshaft Hall sensor

The CDI control module actuates the intake port shutoff motor accordingly with a pulse width modulated signal. This then operates the flaps through linkage. In the lower engine speed and load ranges, all the charge intake ports are closed by the flaps. The entire air mass enters the combustion chamber via the swirl intake ports only. The resulting high turbulence of the air produces a more effective mixing of the fuel with the air and thus improves combustion as well as reducing the amount of soot particles in the exhaust gas. As the engine speed and load increase, the charge intake ports are gradually opened to provide the best possible relationship between air turbulence and air mass for each phase of engine operation.

[The worst possible picture of the intake manifold here]

This sounds like a bitch of a job -- any DIY's would be appreciated!

-Arun
 

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2007 Mercedes 320 Bluetec
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isnahkeri and others: those of you that had intermittent power-loss (i.e. car would be fine on restart), did a replacement of just the intake port shut-off motor (M55) fix it for you? Seems like it wouldn't -- if the motor quit completely, restarting the engine ought to not fix the problem at all. Any more info is appreciated.

Thanks!

-Arun
 

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GL320 CDI - 2008, '04 Touareg V10 TDI, '85 Unimog U1700, '83 Mitsubishi 4WD turbodiesel PU
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snip

The intake manifold contains two intake ports for each cylinder:
* Charge intake port (with flap)
* Swirl intake port

snip

-Arun
I got a GOOD look at the left bank intake manifold when the dealer had to replace it on my car after the tech messed up and broke a hardened steel bolt off in the manifold while replacing M55. There was NO separate swirl port on any of the three 'flap' [read butterfly valve] valves on the manifold I saw. My GL is an '08 but it carries the same OM 642 designation.

In my case, the M55 was replaced because it caused a fuse to blow and THAT triggered a flashing MIL on the dash and several other systems went all goofy because of no electric power. Car seemed to start/run OK but a flashing MIL always makes me nervous.
 

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My 08 GL320 has 64K miles, has been depositing soot on tailpipes for past two to three service intervals. Occasional loss of power but not exactly as reported by others. The Mileage is descent at about 21 city (stop/go) and 25-26 highway at about 65mph. Dealer says normal for diesel. From what I am finding on the forums, US DPF fitted diesels should not smoke. Do the tips look normal or comparable to other 08 or 07 GL320?

https://picasaweb.google.com/113546932926168493599/08GL320SootDepositsOnExhaustTips?authuser=0&authkey=Gv1sRgCNXGiOfkvP7EdQ&feat=directlink
 

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GLK350 2011 Gone, B200 Turbo CVT 2009 Gone, GL320 CDI 2008, B200 Turbo CVT 2006 Gone
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We had 2008 CDI GL and it would release a lot of smoke after service interval done on the highway even trucker were saying to me on the radio about it.

It did it only after every service interval it has to burn something in the exhaust system.

Other issue could be fuel you use.
 

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I have owned my GL 320 from new. On 3 occasions in the last month after travelling approximately 50 miles on the motorway at a variable speed of around 60 to 80mph the power suddenly reduces, it becomes a struggle to maintain 50mph. I have pulled off the motorway and the car over revs and moves forward gaining speed ver very slowly. Pulling over, turning the ignition off and re starting immediately cures the problem, until the next time. The vehicle has just been serviced, there are no warning lights illuninated and everything else appears normal. Any ideas?
We had the same issue with our 2007 GL320 (with only 35,000 km, not miles!) the Turbo's electronic actuator was replaced and problem solved.

This started happening like once a month, then once a week, then once a day...
 

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Hi,

I have an 08 E320 Bluetec, 77,000 miles. My car has the gummed up/carbon buildup on the intake manifolds as well. Here is the history:

1) Oil leaked from a deffective EGR membrane on the swirl motor, and fried it. I had it changed at the dealer ($1200) at about 70,000. Car had gotten a check engine light and the boost was restricted with poor acceleration (semi limp home mode). It was drivable, but not fun (0-60 would take forever and had to shift gears manually to get toyota prius acceleration).

2) Now, 7,000 miles later, the car has gone into limp home mode a few times very intermittently, without triggering the check engine light. Restarting the car clears the problem. Dealer quoted me $4300 to replace both intake manifolds. They do not want to clean them. They will replace the swirl motor under parts warranty, but will not cover any labor.

By the way, I use mostly speedway gasoline from NW Indiana, which does not have any biodiesel. Sometimes I put BP. The mechanic told me to stop putting speedway diesel and to put BP or Shell, as they are higher quality. Sounds like BS to me. In retrospect, I should have insisted that they check for carbon buildup when they had the car apart and clean the intake manifolds if they find problems. I doubt this carbon buildup is from the last 7000 miles. Why did the mechanic not see the gummed up manifolds the first time. Supposedly now my motor is fried again because the valves do not move easily because of the carbon buildup. But when I took the car to the dealer there was not check engine light.

What do you guys suggest? Any hope that MB will step up and cover this repair, on a car with almost 80K miles. I bought this car for longevity, not to replace 4 yrs later.

-Mike-
08 E320 Bluetec
 

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2008 GL 320 CDI
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i am a mercedes technician and the dealer that i work at have seen several cars with the same complaint. the problem we have found with them are the charge air manifold builds up carbon and shorts out the M55 motor for the flaps in the manifolds. i have a car in now with the same complant and will be putting charge air manifolds on it this week. the engine we are having the problems on are the om642 diesel engines.
our 2008 CDI is in the shop now with "stuck flaps" and a leaky oil cooler. 48k miles. Thank you, extended warranty.
 

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1995 e320 wagon, 2009/2010/2011 Sprinter, 1985 300D, 2013 GL450
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The valves will be parked in the open position. When that happens, I'll let you know the results, if any...
Any news? I work on Diesel generators I also do not understand the use of those air intake valves, how complicated will be to disconnect them?
 

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2007 GL320 mercedes, DPF failure

l was told by a mechanic that l can cancel the DPF device in my GL320 Mercedes stop the problem of DPF failure for ever, is this true? is there any implication or adverse effect?
please, advice me.
Jeff
 
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