M103 rough idle and stalling
 

I recently had the top end rebuilt on my 300CE. In addition, I replaced all six injectors, the fuel accumulator and filter. On warm starts the car will crank over and fire quickly for a brief moment and then die. On restart it runs, albeit slightly rough. When I engage drive or reverse the idle seems to drop to around 500-600 rpm and run noticeably uneven. It also feels a bit sluggish off the line. On cold starts is seems to crank a bit long (2-3 seconds) before the engine begins to fire. Any ideas as to what I should look at?

Start by THOROUGHLY checking for vacuum leaks. Check the idle air hoses, the breather hoses, etc.....

Start with the easy + free stuff -- Idle air hoses for cracks and the throttle plate to make sure its at the right height + centered. If you need the PDF for it PM me.

Did you replace the accumulator for this problem or something else?

Has this started after the rebuild? If so, its most likely an unplugged vacuum hose.