Folks, as some of you know I am replacing the CP4 pump in my 2013 6.7 with a 2015 CP4 pump with an Exergy module in it as well as adding a disaster prevention kit at the same time. The replacement went well, I'll post pictures once the truck is back to normal. What's happening is the truck is throwing a P0088 - Fuel Pressure higher than commanded error and going into reduced power mode. I am able to reproduce the issue at will, either at idle, bring the RPMs up to 1,500 and holding them there or while driving. Have let the truck sit there idling for 10 - 15 minutes and the issue does not occur. The truck is tooling along (or holding the RPMs at 1,500) fine. You hear a rattle where the CP4 pump is, feel a shutter, the CEL comes on and the "reduced power" message comes up. Monitoring the actual fuel pressure and commanded fuel pressure you can see the actual fuel pressure shoot up (I'll try to attach a spread sheet, looks like I can). Here's what's happening:

While idling clearing the P0088 code - RPMs between 598 & 630, time index (column A) 22 – 14552 (rows 4 – 419)
Pulling out of a dirt road - RPMs between 630 & 1,067, time index 14625 - 49006 (rows 420 – 1108)
Starting down the road after stopping at the end of the dirt road - RPMs between 1,015 & 1,424, time index 49076 - 72902 (rows 1109 – 1602) truck is normal / actual fuel pressure vs commanded fuel pressure are at most 300 PSI off.
All of a sudden actual fuel pressure shoots up to over 10,000 PSI higher than commanded, time index 72963 - 75093 (rows 1603 – 1641) Stays that way for a short period of time
The truck goes into reduced power mode and the actual fuel pressure vs. commanded fuel pressure go back to normal, time index 75112 - 88917 (rows 1642 – 1900) and stay that way no matter how high the RPMs go, during one test I had RPMs up to over 3,000 after the problem occurred or how long I drive in reduced power mode (which I am keeping at a minimum).

At no point am I exceeding 2,000 RPMs during the attached test, the truck's RPMs fluctuate a bit while it goes through the reduced power process but return to between 1,015 & 1,250. Fuel pressure remains a few hundred PSI over commanded fuel pressure. All other fuel pressure PIDs that FORScan is able to monitor remain consistent before, during and after the issue occurs although the voltage does slowly creep up to 2.31 before the problem occurs, gets as high as 2.4 during the problem but goes back down to between 1.21 & 1.35 after the truck goes into reduced power mode.

As I mentioned, I can reproduce the problem at will so if someone would like to see another PID added to the spread sheet I can easily do that.

Anyone have any idea what might be causing this? Exergy module?, CP4 pump?, Disaster Prevention kit?, Something else?

Have had a number of thoughts on this. It's not leaking, would think that would cause a "low fuel pressure" issue, can't see it being a blockage, if it were a blockage the thought is that the issue would occur again. Thought that a voltage spike might be causing the issue but don't see a spike to anything over what I'm seeing before or after the problem occurs.

Any help would surely be appreciated.

 

Sorry to hear that Chuck. What did the mechanic say? Is he accepting any responsibility at all? What about putting the old pump back in to see if that solves it? That sucks...

I wonder if it has anything to do with it being a 15+ pump on a 13 engine... There has to be a problem with either the new pump, new module or the bypass kit. All three changed and now there's a problem where there wasn't one before. I wish I knew more to give you more help, bud. I hope someone chimes in to help you figure it out.

 

I have the exergy valve and disaster kit on mine with no issues coming up on 2012 6.7 so I suspect issue with new cp4 but only guessing. You might touch base with Exergy and see if you can give some troubleshooting hints on which pid to look at. Sorry to hear about problem and hope you get it sorted out quickly. I haven't researched using the newer CP4 but don't think operating pressures changed between years.

UPDATE to my post. Just read the article linked to replacing the CP4 and a vaneless turbo. It stated the 15 cp4 flows 9% more fuel due to longer stroke so wondering if you are still running stock oem tuning and its seeing incorrect reading due to factory ecm programming? Didn't know if you are tuned.

https://www.drivingline.com/articles...-cp42-install/

 

Chuck is stock I believe. I wonder if the newer 15+ pump with higher flow is giving his ECM fits because it's looking for the lower rated flow??

https://rudysdiesel.com/i-30499193-r...fuel-pump.html

Granted that pump is way more but requires tuning because of the higher flow. I hope this is not the issue but hopefully some one will chime in here.

 

Hey Chuck just trying to help. Here's a video I found on YouTube but didn't watch it. Its over an hour long.

 

CJSSR & Dave, thanks for responding.

Dave,
I need to walk a fine line with the mechanic / shop that I am working with. They have never replaced a CP4 pump before and have never installed a disaster prevention kit. They could have easily said "we've never done that, we're not sure how to do it so nope, you're on your own". They let me know that they haven't done this before. They also let me hang out as if I were an employee during the install. I felt like I was helping my dad, holding the light, collecting the nuts & bolts as they were removed and being the mechanic's 3rd hand when needed. If I make a big stink about it I'll ruin my relationship with them, they will be less willing to "take chances" on "stuff" that they've never done, like the Sulastic Shackles or the 50 gallon fuel tank. The only thing that I can hope for and what I believe I'll get is to be dealt with equitably.

All,
To CJSSR's point, I had seen the "9% more" before but couldn't find the article that mentions it (thanks CJSSR). I did mention this to Alligator Performance who resells the pump with the Exergy module in it. The person I spoke to told me that tuning wasn't necessary. I also sent this along with the link CJSSR posted to Exergy. I'm 100% confident that if this were an issue they will get back to me.

The other thing that I want to mention before I get into the troubleshooting and what the problem might be, I have been in contact with Exergy. These folks are great. Their support has been some of the best support I've ever received from any company about anything. I urge folks that if you are looking at doing something to your truck with products that Exergy produces or resells to seriously consider using them, even if what you need is a bit more costly from Exergy. The additional cost is more than made up for with the support these folks provide should you have an issue. I am in no way affiliated with Exergy, I'm not receiving a thing by talking them up. I just wanted to share with everyone what an excellent company they have been assisting me with the issue I'm having. They even went out, grabbed a disaster prevention kit and tested it in their lab to assist with troubleshooting.

Together with the disaster prevention kit Exergy bought, their testing and the data FORScan produced it looks like they were able to identify 3 possibilities. As I mentioned in my original post I noticed that the "the voltage does slowly creep up to 2.31 before the problem occurs" the Exergy graphed the data. The graph shows how the voltage increases up until the truck goes into reduced power mode. Bottom line is that there is a leak someplace. It is completely counterintuitive to me how a leak can cause high fuel pressure. The 3 potential issues:

1) A missing, damaged or improperly seated o-ring where the disaster prevention kit goes into the CP4 Pump
2) A missing, damaged or improperly seated o-ring where the disaster prevention kit mates up with the Exergy module
3) A stuck Exergy module

Unfortunately I can't get my truck into the shop I'm using until Tuesday. I will be heading there with a 2nd 2015 CP4 pump with an Exergy module in it as well as a new fuel line. It's actually not that unfortunate, without the additional time we would have been troubleshooting in the dark and I would not have had an opportunity to get the parts.

I'll be sure to post pictures along with what the issue is next week after it's fixed. If someone else sees this post and has another thing to check please don't hesitate to post. I'll be sure to look at what you posted when the engine is torn down. Especially if someone is looking to do this and needs a picture or explanation of some part of the procedure.

 

I wasn't saying to make waves with them Chuck. I get it and agree with you. S**t happens. Besides, I was just throwing stuff out there to spur your thinking. That's all.

That is incredible what Exergy did for you. Amazing customer service. No doubt I will keep that in mind. They have already been on my radar.

Did they send you another pump complete w the Valve?

 

Sucks Chuck. Exergy is on the right track with their 3 ideas.

 

If you received a new fuel feed line for the cp4 disaster kit take a close look at it before cutting to length to use with the kit. I ordered a new line set from Ford when I did my kit install and didn't look at it closely before cutting to length. I was going to make the new line up having cut and deburring done and built when I did my install. Unfortunately the new factory line had a manufacturing crimp in the line that would have been a problem with the compression fitting supplied with the disaster kit so ended up using the original fuel line to install and just saved pressure sensors off the cut now useless new fuel line. Sounds like Exergy is a really great company to deal with!

 

Thanks guys.

Dave, Exergy did send me a complete pump with their module in it.
Sorry that I misinterpreted your question about the mechanic. Guess that’s a remnant of my days working at a Fortune 500 company; interpreting questions like that as people looking to place blame. Going to take a while to assimilate back into society.

CJSSR, I’ll be sure to look at the replacement fuel lines I bought closely to make sure they are ok.

Been mulling over a plan of attack for Tuesday. I think I’m going to closely inspect where Exergy thinks the problem is. If we don’t see anything obvious the disaster prevention kit is coming out. I would like to find the problem and keep the disaster prevention kit installed. There is just too much work involved in tearing the thing apart, putting it back together, testing, tearing apart ... Not to mention what wear repeated removal and reinstalling is doing to the stuff we’re messing with.

 

No apology required. That's why texting and email will never replace face to face conversation. You can't put context into the written word. I'd be stressed out after going through all this, believe me. Nothing but good vibes your way bro. Think positive pal...and get 'er done!

 

Well the debacle continues. Just got a call from the garage, mechanic hurt his knee over the weekend and taking a week off. Looks like no truck for another week. They are going to give me a car to tool around with.

 

The replacement fuel lines should work fine if pulling the disaster kit off and installing them in place of the kit. The issue I had was a factory crimp on the new lines the original lines did not have right at the place you are supposed to cut the line to install the disaster kit. Not sure why the replacement lines had that crimp which the original line did not have...Guess Ford sourced the lines from different suppliers. I'm betting the Exergy orings may have been damaged when reinstalling the valve onto the CP4 kit or the cp4 disaster kit orings installed in wrong placement order as the supplied ones with the kit are a different color than the original orings on the fuel line. I installed the Exergy valve and CP4 kit orings using trans assembly lube the it was still a tight fit going into place. That stuff or 90 weight gear oil is what we used to install new fuel injectors into heads during my mechanic years and works very well. Sorry to hear the mechanics laid up for a week delaying getting to the source of this issue.

 

That sux. You have to have Super Duty Diesel withdrawal now...

 

CJ, I think you are referring to an o-ring used while installing the Exergy module into the top of the pump? If so, I bought a new pump that already had the Exergy module installed. I wanted that longer cam stroke and whatever they put on the pump to help avoid ware. Below is one of the locations Exergy told me to check

Dave, no doubt man, I'm dyeing. It was heartbreaking and embarrassing driving the truck home from my friends house having to use the 4-way flashers driving on the shoulder, with silverarados and rams blowing by me. I'm now driving a 1990 something continental with almost 200,000 on it.