kwantum

My 2007 ML63 M156 engine is down with random misfire code code P0300, other codes include:
P0191- fuel rail pressure sensor circuit range/ performance
P0304-cylinder 4 misfire
P0301-cylinder 1 misfire
P0302-cylinder 2 misfire
P0307-cylinder 7 misfire
Basically there are misfire codes for all cylinders
there is a code P0661 not sure what its for..

I also noticed when i start the car it shakes terribly and the driver side exhaust blows out cold air only (Right hand drive).

I have since changed the spark plugs, swapped out the coils, even checked the timing of the cams and still get the misfires..

anyone to point me in the right direction

AMGonFire

I would start with the fuel pressure potential issue first. Check your rail pressures. For me when I have had the same issue a fresh set of primary o2 sensors fixed the problem but I have headers. Common issue.

kwantum

did you have any error codes to show that your O2 sensors had gone out?.

AMGonFire

same codes as you minus the fuel pressure code that was it.

hachiroku

if it's not the ignition coils it's the oxygen sensors. replace both of they're up in age.

kwantum

will give the O2 sensors a try.