Question about 2004 Mercedes-Benz C230 Kompressor

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Yes, i have a c230 mercedes kompressor.

The car knocks and diesels at a low rpm, i unplugged the mass air flow sensor and now it doesn't knock but of course the check engine light is on. does this mean i need a new mass air flow meter?

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  • Scott Carmichael
    Scott Carmichael Apr 22, 2015

    Hi david riewer, I want to help you with your question, but I need more information from you. Can you please add details in the comment box?

    Low RPM...Idle.?..slow speed cruise?...diesels..?
    The supercharger bearings may be going faulty...need more info..unplugging the MAF might put boost system into limp home mode...Code?...I see engine light is on.....



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Not necessarily
when diesels knock and diesel at low rpms it generally indicates a dribbling or leaking injector/s
have an accredited diesel repair shop check it out
If it has some miles on it and the injectors have never been done then the injectors are a fair bet

Posted on Apr 20, 2015

Testimonial: "the car is NOT a diesel. and like i said, when i unplug the mass air flow sensor, it stops knocking so it's not the injectors."

  • Bill Boyd Apr 20, 2015

    petrol or diesel, faulty injectors are allowing fuel into the combustion chamber before and in quantities that s causing preignition

  • Bill Boyd Apr 20, 2015

    same problem as diesels



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Preferably the car is driven in D.
Knocking occurs due to the following reasons:
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