1)Is that the knock sensor?
2)I did see the sensor plastic cover slightly fine line crack, is that an indicator its bad?
3)Also I read in some forum, a way to test the MAF (air mass sensor) is to unplug the cable connecting to the Bosch sensor, is this correct, just to see if I test drive going uphill if the symptom is still there?
4)If so does Bosch just sell the sensor only rather than together with the pipe (save $)
5)I have been using the normal Unleaded Fuel rather than the Preminum Unleaded? Does this have an impact? Is there a liquid to add to the fuel to help compensate this?
6)Cap & Rotor...what's that?
7)There is no Check Engine light. But when I first started the car by pluging back the battery terminal there was a small "thug" noise from the engine compartment. Then the battery when suddenly dead & the fuse 7.5 amp blown for the rear registration plate & the light for the front instrumentation.

But overall I notice more power from the car & much smoother. No more shaking.

8)Will diagnostic scan tool able to pick up the knock sensor or MAF?
9)Do MB give free scan coz I need to top up my Refrigerant for my air cond?
10) Do I need MB to top up or any other specialist can do it?
11) Does Mercedes shop post internationally from US?

Thanks