Hi,
I recently took delivery of this car and the CEL was on. I used a pretty basic OBDII scanner to read the codes. It was throwing P0505, P0507, and P0106.
After driving for about 20 minutes the engine was shaking, and did not feel like it was running well. The transmission seemed to be shifting awkwardly. This was happening at low RPMs and at about parking lot speed (5-7 mph).
Read about possible vacuum leaks caused by loose hoses, thought this was probable because VC gaskets were done recently. I removed the air box and driver side surge tank cover to get better access. Could not find a loose hose / cracked vacuum line in that area. I also noticed that the TB was fairly dirty, so I gave it a quick clean.
I put the car back together and started it up. The CEL was still on, but code P0106 was gone. I still had P0505 and P0507
Tried to clear the codes using OBDII scanner, and I was not able to. (possibly because the scanner is cheap / not meant for MB cars?)

Any help would be appreciated because I'm not super sure what to do

Thanks!

 

Welcome to the Forum. This page does not get a lot of traffic so it may take some time to get an answer. Most of us spend the majority of our time over on the E55 page as there were many, many more of those built. The only real differnce between the CLS55 and the E55 is the outside sheet metal. Post your question there and you will likely get an answers. Go to: https://mbworld.org/forums/w211-amg-81/

 

The CLS55/E55 dont have a lot of vacuum hoses, which is a big plus (simple system)

What are the actual error messages for those codes?

 

The codes I was getting were: "Idle air control system RPM higher than expected (P0507)", "Idle control system (P0505)", and "Manifold Absolute Pressure (P0106)". I did a smoke test on the engine and found that there was a leak, but I could not find the hose where the leak was coming from. After performing the smoke test and putting everything back, I took the car for a short drive and there were no CEL lights, but I did get a "check fuel cap" error 10 mins into the drive. As mentioned earlier, the car was idling rough still and it did not feel like it was shifting right during low speeds. It does feel that the roughness has improved slightly, but it is still noticeable.

 

I have had success using a water spray bottle to find the exact location of the air leak. A little water won't cause an angine a problem and the water will immediately cause the engine to stumble enough to help you to lock-in on the air leak. Also, one area on these engines that frequently causes an air leak is a vacuum hose along the intake manifould side of the left valve cover toward the back third of the engine. It often gets disconnected from its metal pipe during valve cover gasket replacement. I hope this helps.

 

Check the EVAP system. There is a hardpipe which plugs into the back of the supercharger and goes to the EVAP solenoid behind the driver side light cluster. From there it goes to the EVAP canister in the passenger rear wheel well (right above the muffler). There are multiple versions of the EVAP canister. I have the simple version with a solenoid built in.

There aren't that many hoses on the M113k. Are the breather hoses ok? They run from the rocker covers to the throttle body. There is also a small vacuum pipe to the SAI solenoid and both SAI actuators

 

ended up taking the car to a mechanic and they found that the fuel injectors were missing gaskets. They ended up replacing the fuel injector seals, both air intake gaskets, throttle body seal, and resealed a breeder-hose. The serviced and cleaned the throttle body as well. This majorly improved the idle smoothness and shifting, but the car still idles slightly rough for some time after a cold start, but after about 30 mins of driving it idles almost completely smooth. Not sure if this is something to be concerned about.

 

Sounds already a lot better.

No gaskets on the fuel injectors? I think you mean the rubber seals? If so, then you didn't have proper fuel pressure and a pretty dangerous situation with all the fuel around a scorching hot engine + manifolds...You can take a look at fuel trims to see if you are running correctly or a bit on the rich/lean side. Fuel trims should be as low as possible. If it shows around -10% or +10%, then something is up. Below -5% or 5% is pretty good, but again, lower/closest to 0 is best.

 

here is the picture that the mechanic sent me of the fuel rail
how would I check the fuel trims on this engine? Hopefully this could straighten out the little remaining rough idle. The mechanic performed a smoke test after repairs, so I'm not concerned about more undiscovered vacuum leaks.