Cranks over but wont start

Paperclip method? on a Ford? You just count the flashes on the light with the key ON. Anyway, I think I would look at the exhaust.

Disconnect the fuel line at the fuel injector and crank there should be fuel spray if none the pump needs replacement.

Fuel filter,air filter,could be fuel pump,

Sounds like moisture got to the injection system. Put some good fuel treatment in along with more gas and it should take care of it. Also, check air filter for restrictions. Sometimes rodents build a nest in the filter box.

Code 12 means you are in test mode, code 34 is a problem with the map sensor, and code 35 is a problem with the idle control valve.
But those two codes could show up if you disconnect those sensors or if the engine is having other problems.
In situations where the engine stalls, it is very easy to overlook something or assume a component is working.
Treat it like a no start. Pull a plug wire and watch the spark as the engine dies. Use carb cleaner or starting fluid to boost fuel supply.
You'll have to figure out if it is loosing spark or fuel to proceed.
Things like the coil, the stator in the bottom of the dist, or a relay can be the cause. Even low fuel pressure.

I would check the vacuum lines thoroughly as one may have collasped or previous owner replaced with a substandard one,which may be partially collaspe then upon warming up will vacuum itself shut causing the motor to surge then fail to run or start if it happens to be a main line that is affected.

mcdevito75 here, Could be a dirty fuel fliter, remove fuel inlet toarb, crank engine but don"t start, container of 1 pint of gas should pump out from detached carb. fuel inlet, if not replace fuel pump. Very high idle and very low idle could also be a major vacumn leak, check all vacumn hoses, also check intake manifold, spray soapy water around intake manifold try to start, if you see water sucked in or engine now starts, there"s your problem, a vacumn leak.

My truck did this after I replaced the fuel pump. Turned out to Fuel Pressure Regulator. It would crank and crank but never start. It's located underneath the black plastic manifold on the side of the injectors.

Too low fuel pressure. Try spraying starting fluid while someone else cranks it. If it runs, you need fuel pump

check the battery cable connection that is sandwiched between the battery and the outside cable, It runs the computer and if it is corroded, clean it with sandpaper. Mine was loose and corroded and I would stall out of no where.