Intake Manifold P2004 Mercedes-Benz

Diagnostic help for a Mercedes-Benz with trouble code P2004 intake manifold issue. Mercedes-Benz STAR trouble code 0521 diagnosis of tumble flap intake manifold, tumble shafts stick. I have encountered two solutions that worked for me when fixing P2004 on a Mercedes-Benz. One, I apply the repair kit part number (2721402401RPRM). I also replace the intake manifold gaskets and injector seals since those need to be replaced every time they are removed. The second option, is to buy a whole new intake manifold. Please share any questions about your Mercedes-Benz with fault code P2004 and I will share my experience with fixing the issue, thanks.