SDS aka Star Diagnostic System is much more than reader. This is kit version that I use, it would work with your car too.What sds reader would cover my needs?
That's exactly what I was thinking. This doesn't sound like ignition problem. I would start by switching MAF sensors, clear the codes and see what happens.I would look for something common to that side of the engine instead of thinking that 6 coils and 6 plugs went bad at the same time. When I had these codes they were accompanied by fuel trim code for that side of the engine and a purge system code. Idle was rough and I found a vacuum hose off on that side of the intake.
It’s important to remember that the M120 has essentially two separate injection set-ups, one for the left side and one for the right side of the engine. I’d be looking for bad connections or a vacuum leak on the manifold and MAF that feeds that side of the engine - which is actually on the other side of the engine since the manifold crosses over to the opposite cylinder bank.
Yes resistor plugs. I pulled both MAF sensors and cleaned them then put back on. Drove for a while and code has changed from p0300, p0307, p0308, 9,10,11,12. to P0170 Fuel Trim Malfunction (Bank 1). I switched the MAFsensors from side to side and still bank1.It's something common to all the coils like a bad ground or a loose connection to that side's ECU. There are 2 completely separate engine controllers for the V12, one side doesn't know what the other side is doing (by design).
Undo the center engine cover and trace both coil wires for each of the affected cylinders until you find the common ground. Then inspect the ground and the wires.
Remove the electronics box cover on the passenger side of the car at the base of the windshield and inspect, clean, reseat the ECU for that engine side. Use best practices when handling/servicing the ECU. Also, check the wiring to the ECU as it comes into the electronics box from the side. Look for frays, bare wires, anything amiss that doesn't look like the engine wiring to the other side of the engine.
Does the engine currently run resistor plugs?