No start on cold engine

I have a 99 Dodge Ram Van 1500, 5.2 V-8. It has the multi port fuel injection system. The PCM operates the MFI. At cold start it operates in the open loop mode and ignores the oxygen sensors. I have a no start problem. It is the 1st start try in the morning. If I can get it started , it will start right up after the engine is warm. Based on advice, I replaced the IAC valve. That didn't help. There are no codes set.
Here are the sensors that the PCM gets input from in the open loop mode: crankshaft position sensor, coolant temp. sensor, intake manifold temp. sensor, MAP sensor, throttle position sensor, camshaft position sensor. If any of these are defective, a code should be set. I have a code reader and there are no codes set.
Today, I was unable to start the engine. Anyone have any idea why?

I also sprayed starting fluid into the throttle body with the throttle plates wide open. there was no effect at all.
The last time I was able to start it, the engine ran very rough and I had to keep pumping the gas pedal. As the engine started to warm up the idle improved and as the temp gauge went up, I was able to put it in gear and drive normally. Once it was warm, it started quickly and ran normally.
I am leaning to the problem being a malfunctioning PCM. Anyone agree?

Does it take multiple cranks to start the engine? Back when my crank sensor went kapoot, it would take multiple cranks to fire and it would randomly just totally kill while running (kinda scary on the highway!).

Could be as simple as a tune-up. When was the last time the pluigs/wires/cap/rotor were done? It could possibly be an ignition coil on it's way out since the secondary resistance does change a bit as it warms up and this difference may be more exaggerated as the coil wears.

It appears to be a bad PCM. On You-tube I viewed a video called Dodge engine computer repair #2. It was made by Keenan Laws, a computer repair tech and he says the Dodge JTEC computer is poorly soldered and many chips controlling different things come loose. One of the worst is the chip controlling the IAC valve. This computer has a high fail rate and the main reason is the poor soldering by the computer manufacturer. Anyone having a difficult time diagnosing their problem should watch this video.

If your still struggling it may not be pcm, check all your grounds, there is one that goes head to head to firewall that falls but is the main engine to body ground. Also check colloant temp sensor, apparently when they start dying they tell the pcm your 40 below coolant temp and dump fuel to warm up faster

Ive seen many issues with corrosion of the pins in the coolant temp sensor cause this exact problem. Pull the connector off. If the pins are anything other than a shiny metal, the sensor needs replaced.

The wiring on these trucks are strange. For instance the a/c compressor and horn run on the same circuit, but it's not labeled that way. I'd start looking at some wiring diagrams and see what is going to what. But if you sprayed starter fluid into the intake, and no start, that sounds like ignition to me. I'd look in that area.

AZBrazen06 said:

The wiring on these trucks are strange. For instance the a/c compressor and horn run on the same circuit, but it's not labeled that way. I'd start looking at some wiring diagrams and see what is going to what. But if you sprayed starter fluid into the intake, and no start, that sounds like ignition to me. I'd look in that area.

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Not if it's flooding from a bad coolant temperature sensor adding more fuel to flooded cylinder isn't going to help

Mikecollins said:

Not if it's flooding from a bad coolant temperature sensor adding more fuel to flooded cylinder isn't going to help

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So pull the fuel relay, crank it a half dozen times, then spray it with starter fluid. I'm not saying you're wrong, just adding another thought.

Holding the throttle wide open puts it in flood clear mode and shuts of fuel with out having to pull fuses