2010 ML 350 boost pressure issues
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Joined: Jul 2019
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ML350
2010 ML 350 boost pressure issues
Ok here we go. I've just recently replaced the Turbo on my 2010 ML350 bluetec diesel. It was leaking oil and wore out. First test drive and it was nice and powerful but then the Turbo felt like it gave out at 60mph. All kinds of codes including a DPF filter that was clogged. Fixed the DPF filter and got the car running again and it still shuts down at 60mph and the turbo goes to 18%. The code is the infamous 123900 code. This should be a pressure sensor but I'm just not convinced yet. The problem has only grown worse and power is falling off. If a sensor is bad wouldn't it just go out completely? Typically you can shut the car off and it will work again when you start back up.
I've done some research on here ( https://mbworld.org/forums/m-class-w...-123900-a.html ) and other places and it seems there is a rubber seal or gasket on the charge pipe? This could potentially cause the same code. Does anyone have a picture or can describe what I am looking for here or how to test that? We've done a smoke test on the system and didn't find any leaks, but I understand that may not find any either as the pressures aren't comparable.
The engineer in me wants to solve this but I'm feeling defeated. My guess is that the computer puts the car into limp mode of some sort when numbers aren't lining up the way it wants to see. I'm not convinced it's the sensor, but maybe it is and I'm over thinking this?
Here is my vin if that help with anything. 4JGBB2FB5AA586273
I've done some research on here ( https://mbworld.org/forums/m-class-w...-123900-a.html ) and other places and it seems there is a rubber seal or gasket on the charge pipe? This could potentially cause the same code. Does anyone have a picture or can describe what I am looking for here or how to test that? We've done a smoke test on the system and didn't find any leaks, but I understand that may not find any either as the pressures aren't comparable.
The engineer in me wants to solve this but I'm feeling defeated. My guess is that the computer puts the car into limp mode of some sort when numbers aren't lining up the way it wants to see. I'm not convinced it's the sensor, but maybe it is and I'm over thinking this?
Here is my vin if that help with anything. 4JGBB2FB5AA586273
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Joined: Mar 2019
Posts: 145
Likes: 14
Ml350 bluetec
When you reset the code, can you watch your boost live? I wonder at what psi this error occurs.
In terms of boost leaks, often overlooked is the egr pipe and its o ring. It goes from the cooler to just past the throttle body. There was a tsb on it and reccommended cleaning every 40k
In terms of boost leaks, often overlooked is the egr pipe and its o ring. It goes from the cooler to just past the throttle body. There was a tsb on it and reccommended cleaning every 40k
Thread Starter
Newbie
Joined: Jul 2019
Posts: 5
Likes: 0
ML350
When you reset the code, can you watch your boost live? I wonder at what psi this error occurs.
In terms of boost leaks, often overlooked is the egr pipe and its o ring. It goes from the cooler to just past the throttle body. There was a tsb on it and reccommended cleaning every 40k
In terms of boost leaks, often overlooked is the egr pipe and its o ring. It goes from the cooler to just past the throttle body. There was a tsb on it and reccommended cleaning every 40k
Boost goes up to 28lbs if I recall correctly. Boost fine until highway speeds even if I gunn it hard. But I was thinking possibly more airflow at 60mph? Doesn't seem right. Don't know cause I dont gun it at 60. Today it was fine past 60. Tomorrow it may go out at 40 now. Always different now.
