With all due respect I think you are grasping at ideas instead of diagnosing the problem. Things like wires, filters, air box do just suddenly quit without plenty of warning by way of performance problems. The AMM can be eliminated as the problem by merely disconnecting, the engine will start and idle fine without it. It is normal for the battery to run down after repeated cranking of the starter. Make sure battery is charged or use jumpers before trying to diagnose and correct the problem.

To diagnose:
Is there spark at the plugs?

Are both fuel pumps running and lots of fuel in tank. If you suspect intank pump problem because of excessive noise heard from main pump then fill the tank, the main pump can work from a full tnk without the intank running.

Is the cam turning. Just look into the oil filler cap while cranking.

If the answer to the above questions is yes your car will almost surely start. It is a mistake to start guessing and swapping parts, you will likely create additional problems. You should also make use of the cars diagnostics. See 700/900 FAQ section, same for 200 series,

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David Hunter