intermittent car engine vibrations or shaking on 2003 Mercedes-Benz SLK32 AMG

Rookie cbe0621eac06868b3efe0d8d1d3611e23c60d3114864ea2ec19a68cfbd3eebab
This is a very unusual problem and really don't know the cause:

There are a few occassions when I experience random moderate to excessive car body shakes (has to be caused by the engine) when I'm either at a stop sign or on the driveway with the car on idle. I'm not sure if this also happens when driving at freeway speeds (60-70 mph) but I certainly don't notice it or even at slow street speeds (20-30 mph). The car has only a little over 15k miles in it.
(1) Answer
I have the exact problem, somekind of missfires. And no code at all. Sometimes the shake/missfires are smaller, and its rough idle. I had have hade this problem for more then 1 year Now, and have changed a lots of part, sparkplugs, intercooler, sparkplugwires, intake gasket, exhaust manifold gaskets, tryd with lambda, checked egr and checked for vacum leak, checked fuel stuff, changed harmonic balancer(crankshaft pulley) and still dont have a clu. Im going nuts. I think i Will try to change the ignition Coils to se if that helps/patrik