raschick

I'm in desperate need of some guidance. I have a 2009 F150 FX4, 5.4L that has a whopping 224 000km. Over the last couple months a problem has developed that has eluded me and three visits to the dealership.
I'm having extremely rich, smoky start ups and if I put it in gear within the first minute of starting the truck will die. There are no engine codes thrown. I will mention that my passenger exhaust manifold is cracked (which I'm replacing this weekend). Also lately the truck has failed to start on three occasions in the past two weeks. It would turn over but not fire up and no smell of gas. Turning the key on would also not engage the fuel pump.
What I've done so far:

-Replace Fuel Pump Driver Module
-Fuel Pump Relay replaced
-Scanned Truck (no codes)
-Tested fuel pressure (running and static) all fine
-Spark plugs are good
-Throttle Body cleaned

I'm at my wits end with this thing. Has anyone experienced this? Could it be something with the key? (security light isn't flashing) Like I said, I've had it to two different dealerships on three occasions and no progress has been made.