97 PSD IPR problem?

[wcastle]

my 97 f250 started stalling while it was idling, but it would start right up again, now it wont start. i replaced the cps, still no start. i removed the ipr valve, the coil is good and the valve seems to be ok. the pcm is not switching the negative side of the coil to ground. i jumpered the negative side to ground and the truck started. i took it to a shop to have it scanned. the high pressure oil is at 725 psi at idle, but zero while trying to start with the ipr wired to the pcm. i measured the frequency at the ipr connector with the key on, it was zero, there is 12 volts to ground, but 0 volts to the B wire. i traced the wires to the pcm connector, all are good. do i need a new pcm? or is there another issue i am overlooking? should i read the 400hz frequency at the ipr with the key on? i was reading 45hz with the truck idling with the ipr ground shorted.

[harley1rocker]

maybe i missed somthin but ima ask any way...what was the ipr percentage??? should read between 19 and 30% any thing under that is a bad ipr. what kinda scanner did you hook to it? snap on,or auto enginuity?


just lookin at the ipr isnt gonna tell you if its bad,yo need to see the duty cycle

[wcastle]

i think the duty cycle was 14%, i don't remember. i'm pretty sure it wasn't over 19%. the shop i took it to had a snap on scanner. so you say i have a bad ipr?

[wcastle]

when i had the scanner hooked up at the shop, the engine was running with the ipr shorted to ground, that's when it was reading 14%. would that still tell me that the ipr is bad, since it was not being driven by the pcm?