Engine running rough when idle in Drive
 

I have noticed that my car (97 E420) is running rough while idling in Drive. I can feel the vibration by touching the steering column and door panel or dash. The roughness became more appearance when the A/C compressor is engaged. The roughness disappears when I shift to park or neuttral. The car has just got the Air Mass Sensor replaced and the ECU librated three weeks ago. I took the car back to MB and they said that there was no problem.

Doe anyone have similar problem?
Should I clean the Fuel Injectors as they have not been done since MB indicated that no need to do the cleaning if I use premium gas consistently?

What is the best way to clean the injectors?

RE: Engine running rough when idle in Drive
 

it can be fuel injectors.

first is to check the injection time by looking at actual value on every injector (normal is 3.2 ms). then locate which one is worst.

cleaning... you have to remove them all and go to the workshop with ultrasonic cleaner. use alkaline for 1 hour. then change those strainers.