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I just went to an Autozone after getting my first-ever CEL in this car. The readout is
P2015 Intake Manifold Runner Position Sensor/Switch Circuit Range/Performance Bank 1
P2015: The Position Sensor or Position Switch For The Charge Movement Flap (Cylinder Bank 1) Has A Malfunction.
P2016: The Position Sensor or Position Switch for the Charge Movement Flap (Cylinder Bank 1) Has A Short Circuit To Ground.
The car shifts smoothly, accelerates normally, and has a normal idle with no shudders, etc. If the light wasn't on, I wouldn't know anything is wrong.
What does this mean, and what needs to be done to resolve this?
The mechanic I went to recommended I take the car to a Euro shop and replace the entire intake manifold, but since the car is functioning normally, that seems overly expensive.
The mechanic I went to recommended I take the car to a Euro shop and replace the entire intake manifold, but since the car is functioning normally, that seems overly expensive.
Nope. That’s a solution for some other MB engines but not the M271. Probably replacing the swirl flap actuator shown by @TimC300 will solve the CEL problem.
Since it appears that you don’t get deep into DIY, do take it to an MB specialist shop for this.
I don’t really know why they include swirl flaps on DI engines as there’s no mixing of fuel. It’s just air. But I’m not that kind of engineer and it turns on the CEL when it fails, so you have to fix it.
Thanks! I posted in that other thread, and he confirmed the Swirl flap = Charge movement flap and the position sensor is I presume inside the motor housing.
Last edited by e46_connoisseur; Nov 19, 2025 at 12:45 AM.
Reason: mistake
Nope. That’s a solution for some other MB engines but not the M271. Probably replacing the swirl flap actuator shown by @TimC300 will solve the CEL problem.
Since it appears that you don’t get deep into DIY, do take it to an MB specialist shop for this.
I don’t really know why they include swirl flaps on DI engines as there’s no mixing of fuel. It’s just air. But I’m not that kind of engineer and it turns on the CEL when it fails, so you have to fix it.
Yep, I don't have time or the tools to dig around. I will take this knowledge to a Euro shop and see what they say.
Appears confirmed the swirl flap position sensor is in the motor housing. The motor looks to have 5 pins which matches the electrical diagram kindly posted in the above linked thread..
I think with the appropriate Mercedes specific scanner you can see what the sensor is reading, is it within spec or is it not reading at all. Can also actuate the motor it seems 0-100% with the scanner and see if it is functioning.
I was not aware how the M271 intake worked until reading thru the linked thread above. Im familiar with the M272 engine that has swirl flaps and tumble flaps in the air intake.
The shop I took it to claims there is significant carbon buildup in the intake manifold assembly and wants to replace the entire manifold as well do walnut blasting of the valves. Is this reasonable?
I asked about just replacing the actuator, and they said it would break as the carbon build up becomes more severe
Last edited by e46_connoisseur; Nov 26, 2025 at 11:36 AM.
Reason: more detail
If the carbon build up is significant, walnut blasting may be appropriate. I had it done once on mine at 75,000 miles when it was apart for other work. I can’t think of any reason to replace the intake manifold. Seems like that could be cleaned up in the solvent parts cleaner or with carburetor cleaner.
Ok, so the intake valves can be walnut blasted, but intake manifold has to be cleaned in a different manner? Will cleaning the intake manifold with solvent parts cleaner or with carburetor cleaner be any easier? Do you still need to take off the intake manifold (at least you don't to replace it but still the labor costs) and how much extra labor is involved with cleaning it versus installing a new one?
Edit: manifold is plastic so it cannot be walnut blasted
Last edited by e46_connoisseur; Nov 26, 2025 at 01:15 PM.
The intake manifold has to come off to do the walnut blasting anyway. The shop may consider replacing it less expensive than labor to clean it. I don’t know if my indie cleaned it or not. If you clean the intake manifold yourself, stick to petroleum based solvents. The Berryman soak can is too harsh and might cause it to become brittle.
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