Hi all. My engine was running real rough and had the codes read. Thought I was going to have to put it into the shop until I came across this forum. Learned a lot reading posts here.
Ok I have a 2003 c230 kompressor sport with the 1.8L engine. I had the following codes pop up.

P0171 - System to lean
P0620 twice - Generator control circuit
P0128 - Coolant Temp sensor
P0410 - Secondary Air
P2119 - Throttle Actuator Control Throttle body range/performance

What I have done is:
Take out the MAF and clean it out and replace.
Replaced the Coolant Sensor.
Removed EGR and cooling tube to engine and cleaned it out.
Replaced the cross over valve.

The car is running a lot better now but I am still getting a shutter when the engine is cold and the car is stopped in drive or reverse. When warmed up it goes away almost but when I go down the road and just give it a little gas it wants to shutter. If I step on it no shutter. Next step I was going to take was to start going through the vacuum lines and make sure they all are working. It's taken me a week to get all the above done. Single parent working 10 to 16 hr nights. Probably take me a couple of days to get to the vacuum lines.

I know I didn't take care of the generator code but didn't think it would have anything to do with the car shuttering. Need to take it to Napa to test battery and generator. Any help would be appreciated.

 

Has the P2119 fault resurfaced or for that matter have any faults returned??

 

No. And I was kind of wondering about that. I had the codes cleared after I was done working on it and I've driven it like 60 miles or more. Shouldn't the check engine light be coming back on if there was a problem by now?

 

Yes you are correct!! and yes if they return you still have an issue!!

 

But that's the problem. It's still not running right and there is no light showing.

 

Without the appropriate factory or equal diagnostic tools, time and experience you are left with continuing to change out parts and hope you solve the problem,however my wag is that you have a faulty throttle body!!

 

thanks for the suggestion. I was thinking I was taking care of that code by cleaning out the MAF. It was very dirty and oily. After searching some more I can see that I need to try and clean out the throttle body as well. The only problem I have is locating it. On my car the MAF leads to a hose that goes somewhere to the back bottom side of the engine. Cant tell will have to take cover off the bottom later when I get a chance. Doesn't the MAF flow into the throttle body? It seems kind of weird that it would be on the bottom back. I found a video of a c230 throttle body cleaning but it's totally different than mine. here is the link.

 

After looking at it I can see that the tube does curl back towards the front and the intake manifold is under the whole filter and MAF assembly. Man I wish I would have done this when I had the MAF out and was cleaning it. It is such a pain to get to on my car.

Also like to add I'm perty sure that this is the problem. Had oil under the top cover over the spark plugs and when I cleaned the MAF it was realy oily as well as the tube after it.

Picture of my engine - 2003 c230 sport sedan w/1.8L turbo in attachments

 

Well it's been a while but I did get the throttle body cleaned out and man that made a difference. Real easy to get to in the front. Still shuttering though at a stop either in P, R, D. Not as bad in Park though. Still shutters though at all different rpms. Especially uphill. Once the engine warms up to 90c it seems that the stuttering problem worsens while driving but the shuttering when stopped smooths out to just about nothing.
The only code I didn't take care of from the list of codes was the generator code. This shouldn't affect the engine like described should it? Also it never came back after clearing the codes.
Was also wondering if there is some other problem that wouldn't show up on the cel that would affect it this way? Bad head or anything?

 

Did you pull the spark plug boots and see if there was oil in those?
Also, check and see if oil is back in the MAF. It might be that you've got some serious blow by and it is getting back into the MAF.
I am confused as to why you don't have any codes. Did you check for codes or just assume there are no codes since the CEL didn't come back on?