CHECK ENGINE: 2008 C300 Sport Flex Fuel
0524 - The charge movement flap (cylinder bank 1) has a malfunction.
0810 - The air flow of the secondary air system (cylinder bank 1) is too low.
0814 - The air flow of the secondary air system (cylinder bank 2) is too low.
The check engine light only brings these codes up when it is a cold start. I then cleared the codes and it came back on the next cold start. I have since, replaced the intake manifold that comes with everything attached to it and cleared the codes once again. The next cold start, the code came back. I then replaced both air pump control valves and the secondary air pump itself and cleared the code again. On the next cold start, the check engine came back with the same exact codes for the fourth time. Check engine light comes on right about when the secondary air pump turns off after about a minute into the cold start. Tested all the actuators with a vacuum tester and seem to work fine. Can't figure out the problem, any help would be greatly appreciated. Thanks
The codes in question
You should be able to do some active testing/actuation on the charge movement flap with the Autel scanner.
Also, your voltage seems kinda low at 11.83 Volts. Was the car running or do you have a battery charger attached? These cars get wonky when there is low voltage and could actually be the cause of your problems. And because you say it happens on "cold starts" (vs. warm starts when the battery may have a higher charge), you should really have the battery health checked. I know Costco does a stress health check on batteries they sell if you bring it in for problems. So, there may be an auto parts store that will do the same.




"so, only thing I found might have been wrong was the solenoid on vac pipes seemed stuck, with only 8.8v from the car and being 11 years old may be it wasn't moving and a good 12v and actuating a good few times helped.
after 12 months of constant fault " (0524) short or open circuit in sensor lines / mechanical fault of one of the actuating lever / sensor faulty. replace sensor (P2005) " diagnostics saying no issue was ever there ? and it does appear to have a bit more top end grunt that I thought had gone walk about"
No idea what solenoid they are referring to. I just searched "0524 mercedes fault code" and found "w211 Intake manifold fault code...".
It may be this:
Last edited by TimC300; Sep 1, 2023 at 08:41 PM.




I was searching around for causes of that code and someone mentioned a faulty relay. Might be worth checking. I think the relay is under the hood on the drivers side near the brake fluid reservoir.
Last edited by TimC300; Sep 16, 2023 at 10:32 AM.






