I have a 91 F250 with the 302. Last month I replaced both fuel tanks (because they were rusted out), I also replaced both fuel pumps, sending units, fuel filter, ignition coil, spark plugs and wires, and Air filter. Started it up and it had a rough idle, so I wanted to check timing, shut the truck down, and it will not start. Truck cranks super fast but will not fire. ( not a starter issue). Go back out to the truck an hour later starts right up. Still has a little rough idle. I have noticed my thermostat gauge is not working now too. After reading reviews on this forum, I bought a complete new distributor with new pick up coil and ICM and a new engine temp sensor. (The 2 wire one). Start it up, still has a slight rough idle.... and once you shut it off it will not start back up for an hour or 2. So things I’ve checked, I first checked for spark. I have spark at all cylinders from the distributor and I have solid spark from the ignition coil. So I’m good there.... I think. Then I check fuel, I have 10 to 12 PSI at the rail on both tanks, when the key is in the on position, and I have 39 and 40 psi on both tanks while the truck is cranking but not starting. So now I am completely lost. Spark, fuel, no fire? What makes it even more confusing is, the truck will not even sputter with a shot of starting fluid. So is this possibly an ECM problem? Or some other BS sensor (O2, EGR) that is telling the computer to not start the truck? But if the computer is not allowing the truck to start, how do I still have spark and steady fuel? Do I need to replace the engine temp sensor that sends signal to the gauge (1wire sensor)? Could that keep it from firing? I just ordered an OBD1 code reader and will have it tomorrow. I know there are tons of people that have had this problem with these trucks, but I have replaced everything they have suggested, other than the ECM, and have yet to correct the problem. Please help, I am a completely lost!

Jass88, it’s orange.

Jas88,
Why did I not think of that! So if the spark is weak, and we know the ignition coil, wires and distributor is new, could this be a sign of the ECM retarding the spark? Because like I stated in the original post, when the engine is cold, it starts as soon as you turn the key past the on position. It has never started so fast, before I put the new ignition coil in.