So I just bought this truck about a month a half ago and acouple days after buying it noticed a cloud of white smoke on cold starts. I suspected glow plugs or GPR and sure enough my GPR was dead so I replaced that. Didn't fix the problem. Next after researching and testing the UVCH connectors where they enter the VC with an Ohm meter I turned to the UVCH clip being lose. So I pulled both valve covers to find both sides lose and performed the 50 cent mod. Still no marbles. Then the other day I went to pass someone doing about 55-60 and stepped on it hard only to lose power and barely be able to pass them even with my foot on the floor along with my SES light come on for a few mins but all of my aftermarket gauges still read normal(fuel press, oil press, HPOP press, boost) And this has now happened to me twice. Also about the 2 weeks I have noticed that while I'm sitting at stop lights my RPMs will bounce up and down every 5-10 secs just very slightly and it vibrate the truck ever so slightly. The truck is an 02 with 115k miles. DP Tuner that I always run on +70 HP DD setting. Also the truck has a Stealth HPOP, FASS fuel system, wicked wheel in turbo, AFe turbo elbow, AFe intake, and regulated fuel return( Fuel Lab). Other than the things I've stated the truck seems to idle, run, drive fine which is odd to me so at this point I'm pretty stumped. Hopefully you guys can lead me in the right direction! Thanks

 

Does the truck miss? Sometimes tightening the UVCH connections doesn't get it done - I've seen damaged connections. If you click the UVCH link in my signature and test the conductivity, you can put that one to bed.

The tach gets its signal from the Cam Position Sensor - a known weak link on these trucks in the past, and an inexpensive part.

What are you calling normal ICP when you get on it? Does the ICP spike after you let off WOT?

 

Well after turning my dp-tuner back down to stock it is deffinatly idling rough as if it could be a miss but not 100%sure. I do have a spare CPS in the glove box, one of the black old original international parts. I will change this out tomorrow and see if that gets me anywhere. Though if the UVCH still were loose/damaged would the truck still run fine under normal daily driving? And as far as the ICP readings is that my HPOP pressure or how do I tell that? At idle my HPOP pressure is around 300 psi and at WOT it is at 3,500 psi and it does not spike when I let off the throttle. Goes straight down to 500 psi. Hope this helps

 

I don't know if your failure to pass was a miss or a simple lack of fueling.

We can put the HPOP to bed, you answered my question. 3500 PSI ICP? That's aggressive - nice pump. I'm curious what pressure the PCM thinks the ICP is. In other words, if you unplug the ICP sensor at idle - what does your HPOP gauge go from and to (PSI)?

 

So I just got done checking out the ICP, at idle with my tuner on the stock setting I'm getting 500 psi and as soon as I unplug the ICP it goes straight to 0 psi and my check engine light comes on but goes back off 30 seconds after I plug it back in.

 

I am so confused here. You have aftermarket gauges, one of them reading ICP (HPOP). If you unplug the ICP sensor, your ICP goes to zero while running. This tells me you unplugged the sensor for your aftermarket gauge, the HPOP gauge reads something from the OBDII port that I don't recognize, or your engine was magically running with no Injector Control Pressure.


I'm asking the wrong questions, or something is lost in translation.


You mentioned the HPOP gauge reads 300 PSI at idle - that's about 200 PSI too low, and this is exactly what I would expect to happen with a bad ICP sensor on the truck (not your gauge). When the ICP sensor leaks oil and goes bad, it typically "lies" to the PCM, saying the pressure is higher than it really is. The PCM then backs off the pressure command, and the ICP is lower than expected. This makes the truck anemic, barely able to get out of its own way on the highway. If you unplug the ICP sensor on the truck, the ICP on your aftermarket HPOP gauge should jump up to about 700 PSI at idle, and the power should return to your truck.

 

So after taking the truck for a short drive my idle on my stock position on my tu er is still reading 300 psi(200psi low from what you have mentioned above) now when I turn my chip up to the +70 hp setting it idles at 500 psi. Also I bored that while driving the truck on the stock setting on the chip it feels sluggish and doggy. I
Is this pointing to a bad ICP sensor now? Also I've found on a few other threads that the sensor will have oil in the connection? Is this something I should check?

Also, would it be beneficial for me to go have the codes read somewhere since there should be a memory of what code caused the CEL to come on when I was driving it and tried passing that person?

 

Everything points to a bad ICP sensor, but some of the test results you posted confused me.

Some tunes have 600-700 PSI ICP, and stock should be about 500. If you pull the truck ICP sensor connector in stock tune, your aftermarket HPOP gauge (assuming it has its own sensor) should bounce up to about 700 PSI.

If you have a scan gauge/tool that can read the OBDII port, we could look at the IPR signal and clear it all up right quick.

 

So I just went and had the OBDII checked and the only code that came up was P0001 which is Fuel Volume Regulator Control Circuit/Open. What do you make of this?

 

On a Superduty 7.3L? I know of no pressure/flow sensor of any type on the fuel system. What are you using on the OBDII port?

 

That code was read on my local O'Reilys. Not the best but I figured it was worth a shot. Guess not. So what else should I check/look at to narrow down what could be wrong? Or should I just go ahead and try and replace the ICP and hope that fixes the problems?

 

Here's where we are: Your aftermarket HPOP gauge is telling us your ICP is 300 PSI in stock idle. With stock tune, the PCM dose not even fire the injectors until it is "told" the ICP is 500 PSI minimum while cranking - and the ICP sensor is the one doing all the talking. ICP sensors are a common failure at this age, and aftermarket ICP sensors cause more problems. We don't know if the previous owner put an aftermarket ICP in there, or if this is still factory original.

I really want to know what the IPR is, that will be the confirming clue if you have a bad ICP sensor. Unplugging the trucks ICP sensor in stock tune, going for a drive, and watching your HPOP gauge will yield clues as well. This zero reading while the engine is running knocks down that option.

Without the ability to confirm, my educated guess is a bad ICP. You can clean the connector with electrical contact cleaner from an auto parts store, and see if that helps for a short time.

This is the tool I use when I want to know what the engine is doing - including ICP, IPR, Fuel Injector Pulse Width, and many other sensors on the OBDII port.

 

Wish I had a similar tool to use. As of this morning I was was running my +70 Hp tune and at idle it was at 300 psi also. Going to try ad replace the ICP tonight if I can find a part at a local ford dealer and I will report back what happens.

 

That "tool" in the video is just an Android tablet (smart phone can work too) with the Torque Pro app and an OBDII Bluetooth adapter. Dash Command works on iOS portable devices with a WiFi OBDII adapter.