But, you have ForScan with you?
You should be able to read the ICP (HPOP) pressure with that.
Remember, the PCM needs to "see" these 3 important things to trigger he IDM to fire the engine;
1)RPM over 100
2)ICP over 500
3)CRANKING Voltage over 9.5 (in a '99)
And, as stupid as it sounds,,,, make sure you have plenty of engine oil and you're not low on fuel (at 1/4 tank we can run dry with a cracked pick-up)
Got a good pair of hot batteries in it -- voltage check is holding at 11.8+ while cranking. Unfortunately my main problem is I don't have the computer or FORScan with me - my guy who normally does the diagnosis for me is in Kentucky -- I'm stuck in Rockford, IL with the no-start condition.
Finally, just for S&G's, my "Usual" No Start List for review;
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?
WTS light is working - Tach is showing RPM movement during crank - have tested with two different CPS - one "known good"
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?)
Fuel pump and system appears to be operating properly - it refills the bowl almost instantly, and with the drain closed, but lid open slightly, it will build enough pressure to make it "Spray/squirt" a little from the lid.
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.
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).
It's cranking same as it always has - to be honest - batteries got low once in all this, but have portable gas generator and have been keeping them topped up as well as kept block warmer going.
No modified chip/tunes - most of the vehicle is completely stock other than OEM-rated replacements.
ICP plugin/unplug test was one of the initial things that's been tried, and has been re-tried a couple more times after going through other parts just to be sure. It's also been completely replaced - both IPR and ICP are now new (but neither has made difference)
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.
Did reinspect all wiring down there behind the bowl -- nothing is appearing damaged -- most of it was replaced two years ago during another series of repairs to the truck --
Thanks a ton for the list of checks -- I had already been through most of them but the second set of brains and "eyes" always helps like this -- unfortunately I'm not making any progress -- looking into what shops are close in the area that can come do a scan on the computer and find out what's going on...
Was just hoping maybe someone here was in that area that had an adapter and copy of FORScan or something of the likes to get a quick picture of the data-stream from it.