01 wont run

[xViperx]

drove couple hours turned off, returned bout 2 hours later wouldnt run cranked fine, chked fuel,sprk,compression,a few other things,sprayed carb spray bypassed mas sensor ran fine while i was feeding it spray soon as i quit it died,changed plugs chked all fuses an relays,no interia cutoff switch,when i first chked plugs , looked fouled, everything ran good before i did any thing except sprayed the carb cleaner while cranking,then i started going thru the motions , chk this an tha changed plugs an so forth,, secruity light acting normal no codes apparent,, any ideas,,

[GMMerlin]

Did you check fuel pressure? Should be between 52-59 psi.

[xViperx]

yes chked fule pressure , roughly 56 during cranking,3.1 liter,chked relays all fine, chked the fule pump soundes normal , weird tho not sure but, during cranking pump wouldnt kik on but when u turn the motror off it sounds as if the pump is pressurizing again,,,baffled,cuz runs smooth with spray,no knock or mis,soon as u quit spraying it shuts down.

[Retardo]

The fuel pump is supposed to run for another second or two after the engine is turned off. It basically keeps the system "primed".

[GMMerlin]

If you have spark, the next thing Iwould check is injector pulse