Here is my situation:

• Purchased 2004 Explorer 4.0 flex fuel from a local auction about a year ago with 122,000 miles on it.
• Drove it 3 times then after I let the girlfriend drive it while I was out of town it died while she was driving home. Had it towed to the house.
• I hooked it up to my OBD-II reader and had the following codes:PO300,PO305,PO306,PO302, and PO316.
• Started looking around the engine compartment and noticed there had been some critters in there and wires for the knock sensors were fried, so I replaced it, and since I had the upper intake off I replaced all the gaskets.
• As you already guessed it did not help the truck to start.
• I then replaced all the spark plugs and new coil pack, still no start.
• I then replaced the PCV and EGR valve.
• After replacing the above listed items I did get it to start, but it took quite a bit to get it to start and a bunch of black crap came out the exhaust and left a nasty spot on my wall.
• Could not get it to keep running, and I actually ended up burning up the starter and had to replace that as well.
• Thought it could have been something with an O2 sensor and replaced them as well, but still nothing.
• Took it to a local shop they suspected it was a timing issue and wanted and outrages amount of money, so had it towed back to my house.
• I went online and bought all the parts to fix the common timing issues.
• Tore the motor down while it is still in the truck to get access to both front and rear timing chains and they are all intact.
• There is fuel getting to injectors.
• Pulled the injectors which had code issues and did a ohm check on the bench and they are within their range.

Any guidance would be greatly appreciated.

 

I don't know about guidance at this point, but sometimes a few questions open doors to addl thinking.
Did you check the crank sensor and it's wiring?
Was the wrong fuel purchased ?
If you replaced OEM parts with off the wall aftermarket parts could you have introduced addl problems? Having been burned a few times with cheap aftermarket parts purchased on line , unless they are OEM I stay away from them like the plague.
Depending on long it was driven with the misfires now introduces possible catalytic converter problems. We don't know at this point if any damage was done to the PCM with the fried wiring.
You might want to consider some assistance from someone with a quality scan tool to get some important info before spending anymore money and replacing anymore parts.