2004 Dodge Stratus SE, P0300, P0339, P0344 troubleshoot

After 2-3 days of being parked, my Stratus started and operated as usual for 5 minutes, until I accelerated on freeway to 45-50 mph.  Check Engine light illuminated and car "sputtered". I figured just filled tank, it will clear.  After 2 minutes of same symptoms and bigger loss of power, I pulled off freeway.  Acceleration at stoplight was fine until 25 mph. car began to sputter again, but still increased to 40 mph.  The charging system indicator then illuminated.  I was able to get to parts store and ODB scan indicated codes PO300, 339, AND 344.

I let it set over the holiday weekend (5 days) and finally made a test drive.  Started fine, check engine light came on shortly after start, ran good for a minute but sputtered at 25 mph but accelerated to 35 mph fine.  Charging system light illuminated shortly after but vehicle did not stall during short 7 minute drive.

So far I have checked the wire harness pins for Camshaft Sensor, (5 volts and 7 ohms on pins 3 & 2).  All belts seem fine and tight, wires all look in good condition and connected, battery is fine.  Alternator is about 2 years old.  I am now going to check fuse/relays when I find schematic.

So after this, what is my next step?  I do not want to replace all parts. I want to isolate the issue and fix that part only.  Any suggestions on how to further isolate the issue without purchasing camshaft sensor, coil, crankshaft sensor, wires and or plugs???

Thanks.