Truck had symptoms of a bad or sticking IPR at idle the IPR would drop too 4%. I rebuilt the IPR and the truck started up great and the idle had smoothed out. My tablet was having issues connecting to the truck to monitor the IPR that night, so I never got to see what the data was. Ended up driving the truck 200 miles trouble free. After getting to my destination and while idling down the road my truck started to surge again. It persisted to get so bad the truck stalled out. I went to the closest NAPA and installed there IPR and the IPR was at 8% at idle, truck drove fine for maybe an hour then the IPR could barley stay at 4% at idle. I limped the truck closer to the highway and it stalled on me again. At this point I have not really been able to get the truck started. I tried putting an IPR in from Ford and still was not able to start the truck. Key on engine offthe IPR reads 14% and the hpop is reading 220. When I unplug the ICP the hpop jumps upp too 2200, I thought it was supposed to read around 740. I had another ICP from a parts truck I'm not sure on its working condition but when switching with mine I see no difference in the live data. Anything else I should try doing before pulling valve covers. I put a new IPR pigtail on as well.

 

I hate to say, and I could be wrong, but these were almost the exact symptoms I had when Whitey blew the HPOP on me in El Paso. Can you read live data when cranking? If it starts at 300 and jumps to 2700 right away without climbing steadily, that's a good indicator your HPOP is done. Anyway to test the HPOP pressure while cranking as well? I disconnected a line on mine and cranked and the oil only oozed. It had no pressure behind it. Let us know.

 

 

Maybe I'm thinking this wrong but the PCM controls the IPR by duty cycling it via a percent. There is no feedback directly from the IPR to the PCM. If the IPR is at 4% or less it tells me the ICP is reporting to much pressure and the IPR is being instructed by the PCM to reduce that pressure. Key On engine OFF the IPR% sounds normal but 220 PSI is high with no cranking. Like Bryon indicated could be a bad HPOP but will leave that diagnostics up to the experts. Also as Mike mentioned using a mechanical gauge to measure actual high pressure oil might be helpful as using a scanner sometime the values you read are inferred values (open loop) instead of real values (closed loop). Also make sure the IPR is the correct one for your year of truck There are two different versions, one for early OBS and another one for newer OBS trucks.

 

While cranking it starts and stays at 220. It only jumps up to 2200 if I unplug the ICP sensor which I thought was odd because I read it should read 740 when unoplugged.
I like the idea of cranking with the hpop lines removed to see the dribble or pressure. THank you


Good note I only inspected the wiring to where the IPR pigtail meets the harness I will peel more loom back and take a look. I dont know have a fuel bowl anymore I will have too look for a photo to see which connection went into the fuel bowl. Ya a gauge looks like its in order to see whats really going on, if the wiring is fine imo this looks like a bad hpop, what do you think?



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Im sorry if I mis typed I ment to say the HPOP is at 0 with "Key on engine off" but when cranking it jumps to 220.
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I know when originally diagnosing the truck i had 4% IPR and 550 at the hpop at idle. which lead me to a bad IPR.

So cleaned and rebuilt the IPR. After I cleaned it I was not able to get Torque App connected to see what the duty cycle was at that time. But after cleaning and rebuilding my surges at idle disappeared and also the surges when I would be in the accelerator or let off the accelerator also disappeared. I thought my problem was fixed. I drove 200 miles problem free and then everything started going haywire again. With a low IPR % again, I cant recall what my hpop was reading at that time.

The truck still refuses to start. With "Key on engine off" the IPR is reading 14% when I crank it it jumps up to 40-60. The hpop is at 0 until cranked then it jumps to 220. If I unplug the ICP it will read 2220 at cranking.

 

 

 

 

Ok my confusion was that I read when unplugged it should read 740. I thought mine reading 2220 was a sign something else may be wrong

 

Yup, my guess is HPOP. If you want to save the coin, see if you can find a good used 17*. I might can help after I get back home this weekend if you need a hand. Lemme know! I have FORScan, but it sounds yo have something similar.

 

Well I'm kind of in a pickle. I was going to purchase a new HPOP when I decided to double check the IPR part number I was sold by FORD which was 2C3Z9C968BA
I was looking on riff raffs site and turns out this is the IPR for a 94.5-.95.5 with the edge filter. I called back the ford dealer ship and gave them my VIN and he searched it and came back with that part number I was sold being the correct one for my truck. My truck is a 97 though and according to riffraffs site and other sites I checked I should of been sold F81Z9C968AB the IPR for 96-03. The Dealership that sold me the part said they will contact FORD and make sure its the right part number for my VIN, if it turns out to be correct according to ford there is nothing they can do.

Any incite on this? My truck is 97 F250 VIN# 1FTHX26F3VEB80025

 

Your VIN does show as-built data for 2C3Z9C968BA, they are correct, but I think it might be a glitch in the system.

Engine Serial Number Info:
187100 and up take F81Z9C968AB
187099 and below take 2C3Z9C968BA

I am sure you need an F81Z9C968AB but if you want to make sure pull your pump and post up a picture of the front of your pump mounting surface and we can just by referencing it.

 

Is there a way I can prove to Ford there is a possible glitch because they said they have to stick to there VIN catalog and they said basically theirs nothing they can do. I spent 314$ on that IPR because I was out of town and ended up getting towed anyways. I really dont want to pull the pump to find out what IPR I need, is there really no other way?

 

IMHO no I doubt it, they only know what is in the book. I do have an extra IPR if you are in a bind that we use as a tester. If you email us we can see if we can help you out if Ford isn't able to.

 

Won't that IPR work in any year? That was my understanding anyway.