So I am a pretty experienced tech but ran into this problem on my truck and have hit a wall with it. I replaced my intake manifold runner control due to a failed one (tested with the multimeter and it took a poop) so I put the new one in and hit a p2006 code checked the backside and found that it would hit the harness on the passenger side when it opened up half ways. So I had to pull the intake again. I did so and found that the donkeys that installed the engine had messed up the routing for the harness as it between the black coolant line for the heater core and the head. I had to disconnect it from the ecm and the entire passenger side of the engine and reroute it to get it sitting right so I could get good clearance around the runner control. Now I reconnected everything and she will not fire up. I checked and triple checked all my connections, even pulled the intake again to make sure that I did not miss anything. Every connection is good and in the proper place. I am getting fuel as the engine was flooded (plugs were wet with fuel when I pulled one) I managed to get one spark out of the plug while turning over and then nothing, and every now and then when I let off the key it sounds like she wants to start but no go. Stumped here unless the engine is so flooded that the plugs just will not fire. (Plugs are only 2 months old so I can not see it being the issue. All fuses are good, triple checked them. So from what I see it is lack of spark at this point. I hate taking it to a stealership as the donkeys there could probably not do any more than I can. No codes either while cranking.

 

So as an update I pulled the fpdm off and found a nice deformed mount plate and hole in the backside of it. Ordered one today and hopefully that is my problem. I have power on my coils I verified that this morning.

 

installed the new fpdm and unfortunately still no start, isolated it to no spark or lack of spark, is it possible for my crank sensor to fail but not throw a code?

 

Solved the problem. I had also replaced the plug for my crank sensor. Turns out it is polarity sensitive. Swapped the wires and now she fires up like a champ. So pumped that I found the issue and got it fixed.