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Repeated code issue

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I just cancelled my order for a new 2019 3500 H/O. I happened on some info on the CP4.2 pump failures, and the more research I did, the worse it looked. It is a straight up piss-poor design.

While I don't know the details, page 58, Issue 104, Technical Topics by Robert Patton in the TDR goes over the details of the new '19 Cummins HO engine. He spoke of the fuel pump. "This Bosch "CP4" used by Cummins is not the same as the Bosch unit used by Ford or GM."

I wouldn't lose sleep over this yet.
 
I’m not loosing any sleep! That CP4 has been out for a long time, and to think Bosch has turned a blind eye to the failures, and Cummins had no knowledge of them going into this venture seems a bit absurd.
 
I just cancelled my order for a new 2019 3500 H/O. I happened on some info on the CP4.2 pump failures, and the more research I did, the worse it looked. It is a straight up piss-poor design. I'm referring specifically to the pump cam and roller lifter design. When compared to the CP3, the almost guaranteed failure of the CP4.2 is obvious. Two of these pictures show the failure point of the pump clearly:

View attachment 115115

View attachment 115116

View attachment 115117

In the first two pictures, you can clearly see how the lifter has rotated in the pump bore, and once that happens, the roller quits spinning and begins acting like a knife on the pump cam lobe. You will never know this is happening until the metal shavings have traveled throughout the fuel system, and finally plugs the pump with debris, shutting down the engine. The third pictures failure looks to have been caused by metal debris seizing the lifter in the bore, and that caused the catastrophic failure. $10K - 15K please! That's if they try to blame the failure on fuel contamination and deny the warranty. The CP3 pump cam and lifter design is near bullet proof compared to the CP4.2. When the CP3 wears out, there's no collateral damage.

As far as changes or upgrades to the newer pumps, only different coatings have been applied to the bore and lifter to lessen the wear. It sure doesn't look like those new coatings worked!

I contacted Cummins last week about the pump failures, and asked if any attempts have been made to fix this issue, specifically regarding the 2019 Rams. They responded with a one sentence email. It stated simply, "You will need to contact Dodge to see if they have any updated information on the pump."

Although I understand their response, it is funny that they defer to Chrysler. Bosch doesn't provide any info on the pumps either. Also, it does not appear that Bosch has vehicle brand specific CP4.2 pumps. A CP4.2 pump is a CP4.2 pump. No variations.

It is my understand the Edlebrock holds a patent on preventing a roller cam follower from turning in a bore and Bosch refuses to pay to use the technology.
 
https://pocketmags.com/us/diesel-world-magazine/june-2019/articles/554048/why-the-cp4-2-fails

And another view....

BOSCH CP4.2 A COMPACT, EFFICIENT PLATFORM THAT’S HERE TO STAY
  • Diesel World
  • 2 Apr 2019
#ad



While most of us know the Bosch CP4.2 because it’s what came on our LML Duramax or 6.7L Power Stroke, this high-pressure fuel pump has been around awhile. With 39,000 psi (2,700 bar) capability, the CP4 can meet even the most stringent diesel emission standards, and it’s been used in conjunction with both piezo- and solenoid-style injectors in dozens of passenger car makes and models all over the world. To date, more than 40 million CP4S have been produced, with its modular design allowing Bosch to grow (CP4.2) or scale down the pump (CP4.1) based on the OE’S fuel system requirements and packaging needs.

The Bosch CP4.2 debuted in the North American truck segment back in 2011 on both the 6.7L Power Stroke and the LML Duramax, although a similar version (CP4.1) had already been brought to other markets (such as Volkswagen, BMW and more than 20 other brands globally). Fast-forward eight years, and it’s in use in most diesel engines in the truck world.

Although GM moved on to the Denso HP4 pump for its L5P Duramax in 2017, you can still find the CP4.2 aboard the aforementioned 6.7L Power Stroke, the 3.0L VM Motori Ecodiesel in Ram 1500s, the 5.0L Cummins in the Nissan Titan XD and now, even the new 6.7L Cummins uses one. One thing’s for sure: This pump isn’t going anywhere anytime soon.
 
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While I don't know the details, page 58, Issue 104, Technical Topics by Robert Patton in the TDR goes over the details of the new '19 Cummins HO engine. He spoke of the fuel pump. "This Bosch "CP4" used by Cummins is not the same as the Bosch unit used by Ford or GM."

I wouldn't lose sleep over this yet.
Well, if it is true, and I am not saying it is not, why haven't they explained what is different? They published all sorts of videos for new features for the new trucks, some of which were left out of 2019 trucks, yet they can't address this?

Sag2 is supposed to have some info in the next TDR, and I am looking forward to it.
 
Well, if it is true, and I am not saying it is not, why haven't they explained what is different? They published all sorts of videos for new features for the new trucks, some of which were left out of 2019 trucks, yet they can't address this?

Sag2 is supposed to have some info in the next TDR, and I am looking forward to it.


One change is a filter that is supposed to keep metal fragments from destroying everything downstream from the pump. It is supposed to shut down the engine before downstream damage occurs?
 
One reported culprit is air in the system????

Can the dealer even consistently keep air out of the fuel system when changing 2 filters???
 
Hmmm, I have CP4s on My bench that have over 500K Miles...its failures are related to contaminated fuel...Install the correct Auxiliary Filtration ( not the popular systems you read about at this site or the web ) the 2019 system on Rams is robust and should prolong the CP4 life, The ONLY guarantee of CP4 /CP3 Pump survival is correct Auxiliary Filtration, If you put faith in the systems that are so proudly spoken of on the WWW its just time before disappointment and bank funds departure.

This is all contingent on CONTAMINATE FUEL the Ram system will filter dirty fuel well. X % of the contaminated fuel will bypass Rams system and by the time the Truck give's any type of warning or poor performance it will be to late. $$$$$

Contaminate fuel will destroy any HPCR system, the Problem with CP4s is its more of a particle maker that by design send those particles to injectors. We don't have the conversion now , in the future we will...

Those Bypass system that a few offer to protect Injectors will fail also when contaminate Fuel is used.

All of the info that is promoted Through Ram is outdated and irreverent.

The only reason I don't have 2019 6.7 is not because of the CP4, I want the NON-External EGR engine. Ram ,Ford, GM can fool somebody else by covering it up. Even thou the New engines use very little EGR gases I hate seeing in on the engine.
 
One reported culprit is air in the system????

Can the dealer even consistently keep air out of the fuel system when changing 2 filters???

I don't see air connection to failure. If air enters the system and cannot be evacuated VIA COV circuit the engine will die and need to be restarted ( 2-3 times) until the air is gone VIA return circuit.
 
I don't see air connection to failure. If air enters the system and cannot be evacuated VIA COV circuit the engine will die and need to be restarted ( 2-3 times) until the air is gone VIA return circuit.

This is what one source claims:

With its ultra-tight tolerances, the CP4.2 does not tolerate anything other than diesel fuel very well. However, what is the most commmon unwanted contaminant? Air. That’s right—aeration is the number-one “killer” of these pumps. Whether it is from lack of maintenance, running the truck out of fuel, improper fuel filter installation or not allowing the fuel system to properly prime after a filter change, nine times out of 10, air is what takes out the CP4.2.

I don't know how accurate it is
 
Newsa its Not accurate.... I could run any CP4 dry 250 times restart the feed system and watch all the air evacuate. You would never be able to run any engine mounted CP4/CP3 dry equal to my test Bench. If I had the Time after that 250 Time run and tear down you would not be able to detect any wear. Their is always residual fuel left in the system for lube after fuel filter(s) change, and if you allowed the lift system to operate 15 seconds prior to starting at least 50% of the air will evacuate ,thats plenty of fuel for lube cranking to start.

The matting surface tolerance are equal in both pumps .00000/ -02 -04
 
"The only reason I don't have 2019 6.7 is not because of the CP4, I want the NON-External EGR engine."

Like this???

fullsizeoutput_2418.jpeg
 
No, That is too bright of a red paint job - it will clash with the body color on my truck.

I can see how constant aeration would cause damage - it does with many hydraulic pumps. But if that were the case I'd suspect you would see other issues too.
 
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