mercedes c270 inlet port shut off

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V4LL3Y

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hello im new to the site ive been browsing round a bit what it is i am asking for a bit help if possible.there is a fault on my friends car which we have been trying to fix i no it is the inlet port shut off motor well actually its the linkage has come off but cannot get it to stay on and is very awkward to get your hand in place to push it on but i was wondering if i jammed the flaps open on the inlet will it still run ok with the motor still wired up but leave the arm off that connects from the motor to the linkge it seems quite a job to change the inlet and costly to so does anyone no if this would fix it temporarliy thanks in advance for any help p.s it runs amazing when its right lots of power etc then loses it after a short journey when easing of the throttle
 
The push in ball joint may be replaceable with a nut and bolt with washers maybe? Other than that I would try ebay, there are some manifolds knocking about and I'm sure the arms are all the same.

If you leave the flaps open it will run like a bag of ~@:*!! and run real lumpy on idle because the movement of air has slowed down in the manifold and the swirl pattern for the air will be irregular.
 
The push in ball joint may be replaceable with a nut and bolt with washers maybe? Other than that I would try ebay, there are some manifolds knocking about and I'm sure the arms are all the same.

If you leave the flaps open it will run like a bag of ~@:*!! and run real lumpy on idle because the movement of air has slowed down in the manifold and the swirl pattern for the air will be irregular.

Not true actually.

I jammed one open for an experiment and there was no difference in the way it idled or drove.
 
Not true actually.

I jammed one open for an experiment and there was no difference in the way it idled or drove.

must agree with olly here, the actual flap position will make very little difference to the running of the car, no noticable change at idle what so ever, and just a little black smoke at full throttle. the thing that will put it into limp home though is when the m55 servo motor does not move to its controlled position, this will always cause problems whether the flaps are connected or not.
 
must agree with olly here, the actual flap position will make very little difference to the running of the car, no noticable change at idle what so ever, and just a little black smoke at full throttle. the thing that will put it into limp home though is when the m55 servo motor does not move to its controlled position, this will always cause problems whether the flaps are connected or not.



Sorry for bumping an old thread,but would a 320 slk have these flaps in the inlet manifold,My car makes a loud sucking noise when you lift off the throttle and could any of these flaps be stuck open/closed and cuase this,
 
I'm having my inlet manifold and stepper motor replaced at a cost of £700ish by an indie next thursday....it's the only way (i've been told) to get the car out of limp mode.

mine's a c270 diesel as well.

..Steve
 
I'm having my inlet manifold and stepper motor replaced at a cost of £700ish by an indie next thursday....it's the only way (i've been told) to get the car out of limp mode.

mine's a c270 diesel as well.

..Steve

:eek::eek::eek: Just before christmas I had the same go on mine (inlet post shut off motor) merc dealer wanted silly silly money to do the job. In the end I bought the part for £97 and did the job myself - Took me two nights but got there in the end.
I feel your pain.
 
Hi Simddyboy
I am just about to do my inlet manifold on my C270 Did you have any problems that I need to look out for, Did you need to remove the fuel rail ?
 
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No need to remove the fuel rail ( not on the 3Ltr v6 anyway), just the covers, air intake, turbo and turbo pipes. I had to remove the plastic wiring harness holder to allow a bit more acces but I'm not sure of the layout of your engine.
A small pick up took would help because no doubt you will drop the small clips that hold the connecting arm at least a couple of times.

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I didn't notice your removing the inlet manifold.... I didn't need to remove mine as the shut-off motor was in between the 2 manifolds, you may need to remove your fuel lines after all but someone who had done this job on the 5 cylinder will need to confirm....
 
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Yep mine is the 5 cyl engine, I am replacing the manifold as it is dripping from the shutoff ports I have all the parts just need the push to go do it. The trouble is the more you read the harder it gets
 
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Can you show me where this motor is on my engine, is it what ive circled? mine has also gone and allegedly caused my an oil leak from the airbox. any ideas where the airbox may have leaked oil? cheers

any suggestions where to get the motor?
 
The inlet port shutt off on the V6 Diesel is a completely different job. Get the parts from MB and expect the exhaust manifold bolts to snap. They always do.
 
the c270cdi is a straight 5 cyl engine what i have done many times is remove the manifold beat the flaps out thread the holes and put in bolts with instint gasket so its just a straight manifold put on a new stepper motor as the old one sticks and the control unit gets high resistance puts it into limp mode the new motor doesnt move any flaps but the control unit thinks it does car will be flying
 
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Can you show me where this motor is on my engine, is it what ive circled? mine has also gone and allegedly caused my an oil leak from the airbox. any ideas where the airbox may have leaked oil? cheers

any suggestions where to get the motor?
the unit circled is egr valve the inlet shutoff is below the turbo in the centre of the V
 
Thats interesting Murray Motors!
Does this really work? I have this problem on my 2003 clk 270cdi, and it will save a nice wedge if it works. Hopefully I might be able to get the linkage back on without taking the manifold off but if I have to this could be the way to go.
 
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I have done this flap removal mod on my 2003 c class 270cdi and book says that you have to remove the fuel rail, you don't. With a little jiggling you can get the manifold off. I also blocked flap holes up with 16mm bolts but just removed linkage from motor as it was OK. Still working well 12 months on and no clouds of black smoke on acceleration.
 
On the v6 you can change the motor with the turbo on. Saves on snapped bolts but you do have to be quite heavy handed tbh
 
Thats interesting Murray Motors!
Does this really work? I have this problem on my 2003 clk 270cdi, and it will save a nice wedge if it works. Hopefully I might be able to get the linkage back on without taking the manifold off but if I have to this could be the way to go.

Hi, I copied the "Howto" below from another place......
Many have done it on the other forum and there seems to be NO ADVERSE EFFECTS...

A popular mod now, is to disable the inlet port shut off flaps, particularly on 270 CDI (612) engines.
This is usually done because of damage to the flaps from wear and tear, accelerated by EGR gasses.

It is possible to replace the entire manifold, but at significant cost, and some of these cars are old and unloved now!
Even if the manifold is changed, problems can still occur with the actuator motors (M55) jamming and signalling faults to the ECU.
So, how to do without the system...

To remove the flaps is simple, but leaves big holes in the intake manifold.
To plug these holes, I cut short sections of 16mm threaded bar, tap threads in the holes, fit the plugs with superglue, and finally drill and lock wire them for good luck.

With me so far?

But we still have a problem, if the motor is removed, a fault code will be logged, stating 'M55 inlet port shutoff motor signal wire resistance too high'.
Yes, the motor can be left in place and connected to the loom, and if working there will be no fault code.
However, as is often the case, the motor may have heavily worn gears, and frequently jam.
This will log a different code - 'M55 inlet port shutoff motor signals fault through ground keying', which simply means the integrated circuitry in the motor has seen that its mechanism is jamming, and has signalled a fault to the ECU by temporarily grounding out the signal wire.

So, if the motor is worn and jamming, we have a problem, but we do not want to replace it with a new one, especially now there are no flaps fitted.

Getting there now...

So, to cut to the chase, all we need to do to avoid logging fault codes, is wire in a resistor between the signal (PWM) wire and the 12v wire to the M55 motor.
4.7k Ohms works well..
 
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