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6.0L Power Stroke Engine and Drivetrain Discussion of the 6.0L Power Stroke diesel engine and drivetrain in the 2003-Up Super Duties and Excursions. No gas engine discussion allowed except on transmissions and drivetrain that pertain to all models. Please confine discussion of topics in this forum to those items that are specific to the 6.0L Power Stroke engine.

Thread: ICP Issue? IPR Issue? Other? Need help troublshooting. Reply to Thread
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  Topic Review (Newest First)
09-03-2019 06:50 PM
ArcticDriver Great thread!
09-03-2019 02:06 PM
iqraceworks ****FIXED IT****

Well, I think I fixed the problem. It was either in the butt joint splices where I had connected the aftermarket ICP pigtail connector last year, or the internal terminals of the connector itself.

I got my new Motorcraft ICP pigtail connector in Friday. I cut the old aftermarket connector off, and soldered on the new Motorcraft connector, and then heat shrinked the solder joints.

Over the weekend I put about 500 miles on the truck with the new pigtail ICP connector. The truck ran great, I didn't have a single issue.

Just another example of why it's better to spend the extra money up front on these trucks and buy the genuine Motrocraft part vs. the cheap aftermarket stuff.
08-28-2019 05:55 AM
iqraceworks Thanks for the info. I went ahead and ordered a motorcraft ICP pigtail connector. I did put a new pigtail on the truck a couple of years ago.....but it was some cheap aftermarket one off of eBay. After doing a little research on them ...it sounds like they are prone to have issues with the terminals inside the plug (like you mentioned).

I figured that replacing the pigtail would be the next logical step.
08-28-2019 05:08 AM
ford_doctor I think I would like to get my hands on it with my IDS. If you did not replace the ICP harness connector when you threw a sensor at it you should have... to eliminate it as a possible cause. Connectors have been known to cause problems. (I apologize if you did and I missed it above) As for the parameters you are reading, I have been told several times over the years that the PIDs we can access in the field are filtered and I have seen evidence of that. Once had an ICP voltage reading that did not match what I measured by back-probing the sensor or using a breakout box. .
08-27-2019 12:55 PM
iqraceworks **UPDATE**

Hopefully this might help with troubshooting.

So today during lunch, I decided to go out and sit in my truck to play with Forscan a little more. Just as it happens, as I was in my truck with it in park and idling nice and smooth (rpm:690, ICPv .86, IPR % 22.8, HPOP 580psi)........it started doing it's right idle thing.

The HPOP pressure was bouncing all over the place, the RPMs were bouncing all over the place, the Desired IPR rate was bouncing all over the place........but the ICP voltage was nice and smooth, almost not moving at all. With the HPOP pressure jumping around, shouldn't the ICP voltage have been jumping around also?

So was the truck just using the default ICP voltage because it had a funky ICP sensor connection? Maybe not a 100% break in the wire(s).....but a "less than idea" connection? Would that not set off a fault code? The truck was idling so rough, I thought it was going to die. The whole thing was shaking...it's never done it that bad before. I with I would have gotten a video of it all....but it stoped and went back to a smooth idle before I could get my phone out.

So.....what do you think?
08-27-2019 07:15 AM
iqraceworks Well...it did it again this morning. Driving down the road, let off the gas...and the motor revved up on it's own like I mashed the gas for a split second. It sure does act like an ICP sensor issue.

I wonder if there could be an issues with the pigtail or connector?? If I completely disconnect the ICP connector, it throws a code.........would a quick bad connection throw a code? That's the strangest part.......even after this thing does the high idle for a minute or two, and rough idle...and the "auto-rev" like this morning....no codes.

Maybe I will go back to the stock tune........I'm pretty sure that some of the "custom" tunes out there will suppress some of the codes the ECU tries to throw. Back when my turbo was sticking.....I would get a low boost code when running the stock tune, but no codes when running my IDP tunes.

I think I might go back to the stock tune....see if I get any codes that might help me out?
08-27-2019 07:01 AM
iqraceworks Seems like it's doing it more frequent now. On the way to work this morning...pulled into the gas station, let off the throttle as I'm slowing down......and the motor reved up a little bit on it's own....like I mashed the gas just for a split second. Startled me a little bit. Then it acted fine again. When I was leaving the gas station a few minutes later, I let off the gas and get the rough idle thing.....and also a high idle. I get on the highway, and then everything acts fine, all the way to work.
08-24-2019 05:05 PM
iqraceworks Yep....no codes.
08-24-2019 01:56 PM
jimmy Have you scanned for DTCs again?
08-24-2019 10:44 AM
iqraceworks Thanks for the tips on what wires to check. The problem I'm running into is that when it happens.....it only happens for a short amount of time, and then goes back to running like normal. I haven't been able to make it home yet while it's still acting up. I would love it if the problem happened long enough so that I could actually make it home and get my multimeter put and start checking stuff.

I just got back from a 45min drive this morning.....didn't skip a beat, not a single hickup.
08-24-2019 09:47 AM
jimmy If IPR were to stick close the injection knock gets LOUD and it runs rough. The values and idle speed sound like default for no ICP sensor input but that should give DTC for ICP sensor. You aren't getting that code from what I gather from the thread. So at this point I would monitor the 5V reference you will find at ICP sensor. Use a T pin if you don't have a pointed DVOM probe and insert it next to the wire down into back of connector. You don't puncture the wire, you push the pointed tip through the rubber connector body seal and it makes contact with the metal terminal. I can't recite the wire color but probe until you find the one that is 4.95-5.05 volts. Run a long wire, it can be tiny gauge speaker wire for this purpose, and attach to the DVOM and read that voltage if it begins to act up. If it is more than .3V below the 5V spec then it will mess up the output signal. If it is higher that offsets the signal too. Other sensors share the 5V source in the PCM and you can find it when it is acting up by un plugging the other sensors. The exhaust back pressure sensor has done that for me a couple of times and did not set a DTC. Someone may chime in with the sensor groups so you don't fool with ones that could not affect the Vref for the ICP. I have not had a bad pedal sensor on a 6.0 yet but if it acts up you should look at aceel pedal PIDs. Again, I would think any disagreement between the redundant accel pedal sensor inputs should set a DTC readily.
08-24-2019 07:37 AM
iqraceworks Well, the problem happened again today on the way home from work. And it did for a pretty long period of time, so I was able to get some numbers on the PID's and more info.

So as I was driving around 55mph, the truck felt like someone had just quickly pressed the gas pedal for a spit second...just a quick jerk. It did it a few more times after that. The Throttle Position PID reading stayed steady when this happened, right around 20%. So the ECU wasn't sensing that I was calling for more throttle.

Then after a few miles, I let off the gas to make a turn....and I noticed that as I let off the gas the injectors sounded a little funny, and the truck wanted to idle fast. It held the idle at around 920rpms (usually it's around 650), my IPR rate was at 34.0% (usually it's at 22.8 during idle), and my HPOP pressure was 640psi (usually it's around 580 at idle). FICM voltage was 49.0, and battery voltage was around 14.2v. Even after getting on the gas several times, every time I let off.....it would fast idle. But, the idle was smooth...not rough an erratic. Just a higher than normal idle. Could the IPR be sticking? Not sure why that would explain the weird injector sound though while I was off the gas and coasting.

I drove for a mile or so, and the truck just felt weird. Every time I would let off the gas and coast the injectors would sound weird (like every other one was off or something), and it would idle fast. When I would get on the gas, everything would sound normal......but it just felt odd.

Jut as I pulled in the driveway thinking I could finally do some troubleshooting......I feel the idle drop back down to normal, and everything is fine. I couldn't get it to duplicate it no matter what I tried. Like before, I scanned the ECU...no error codes. I ran through all of the PCM, and Injector Click tests that I could run with Forscan, and they all showed good. I could hear each of the 8 injectors click like they should, nothing sounded odd.

After the idle went back to normal, I climbed up on the truck and pressed around on the FICM connectors, every section of wiring loom I could find, and every socket and electrical connectors and sensor I could find....nothing. No blip in the idle, no increase or decrease in idle speed....nothing.

With this new info, any ideas??? Would a bad ground cause this higher than normal idle issue?? Could this be a sticking IPR? That might explain the high idle, but it wouldn't explain the strange injector sound. Failing FICM?

Thanks so much for the help guys!!
08-21-2019 04:56 PM
bobofthenorth It sounds to me like a wiring connection and my rule for 12V troubleshooting is "Its always the ground" so that's where I'd start. On a ~15 year old truck its not hard to imagine a few bad ground connections or maybe even entire missing straps.
08-21-2019 12:21 PM
Originally Posted by dillon134 View Post
Get a new ICP Sensor. Like you said, if it isn't the root cause of your problem, at least you'll have a spare. It's such an easy fix if it's the problem so why not take a chance.


Well, I put in a new ICP sensor just for the heck of it. It's been a few weeks, and several hundred miles....and more more random "funky idle for a couple of seconds" type issues.......until today.

So, same as before.....I'm on the highway driving along. I let off the gas as I get off at the exit and start slowing down. And the motor does that "chug,chug,chug" type idle for 2-3 seconds.......and then it goes away and idles smoothly. It happened to fast, I couldn't catch any of the readings on the HPOP, ICP, IPR off of my Torque PRO app. Scanned the truck again with both Torque pro and Forscan...nothing. All it good.

It's frustrating tracking down stuff like this. I wish it would happen all the time, or do it when I'm at home and can spend some time looking at all the PID's.....but it only goes it when I'm out on the road, and just for a couple of seconds . Very odd.
08-06-2019 12:53 PM
Originally Posted by dillon134 View Post
Get a new ICP Sensor. Like you said, if it isn't the root cause of your problem, at least you'll have a spare. It's such an easy fix if it's the problem so why not take a chance.

Thanks, I'm thinking the same thing. At least I will know that's one less thing that could be causing the problem.
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