The first thing I would do is to measure your Voltage while cranking
. Static voltage is really meaningless.
Next, you want to be sure it's cranking fast enough
(sometimes sounds that way, but may not be).
Since you brought up the Starter and Solenoid, I'd start there because the PCM needs 2 thresholds to be crossed before it will trigger the IDM to fire the injectors. One is RPM, it has to be over 100 (about 150 is normal, there's not a lot of difference to your ear). And the next is the voltage level as you are cranking (in an '01, with a fender mounted solenoid, you need to be over about 10V)
After that, My usual No Start -
WTS Light? - do you get it when you first roll-on the key? (shows the computer is running)
Do you see cranking rpm on the Tach? Do you have a spare CPS to try?
Is there fuel in the fuel bowl now? Does it refill after cranking? (open the drain lever to check) Look above the pass ft tire, you'll see a 3/8" metal tube, against the motor that ends there, it's the drain for the bowl (yellow lever you slide to the side). Get a cup, open the lever, drain the fuel bowl, look at the fuel, close the lever. Then, turn the key to the ON position (should hear the pump) for 15 secs. Drain the fuel bowl again, whaddya got?
Can you hear/feel the pump running (below the dr seat, against the framerail)
Could the fuel gauge be giving a bad reading? (Below 1/4 tank?)
Is it cranking fast enough? - it won't even TRY to start if cranking too slowly.
Is your truck "chipped"? If so, remove it as a Test.
Fuel - pump runs? Fuel refilling filter housing? (open the yellow drain lever to find out)
Tank below 1/4? Could the fuel gauge be giving a bad reading? (are you close to empty?)
You can unplug the ICP sensor, as a Test, so the PCM sets a default value for the IPR to run on (expect this to set a new "Low ICP" code, don't let that misdirect you after a scan).
Did you check the plug and sheet metal nut going to the IPR? That nut can vibrate off and allow the solenoid going over the valve to slide around. The wires going to the IPR can get brittle, crack, and short together. Make sure the plug & wires look in good shape.