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Recall of High Pressure Fuel Pump

c3k

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RebelGuy2020, I'm gonna give him a call sometime this week just to confirm, but from what he told me, the recall is only on the pump, a Bosch CP4.2 (please correct me if I'm wrong.) He didn't say it was a different pump, just one manufactured outside the window of error they have discovered. So I'm thinking it may come direct from Bosch or possibly from the Sterling Heights Ram Truck plant in Michigan.
Having seen the video, linked upstream, I would PREFER to retrofit a Bosch CP3 style pump, since it eliminates any chance of this particular failure.

How does the later CP4.2 differ from the earlier ones? (<- No, I don't expect you to have the answer, but maybe someone does.)
 

Brutal_HO

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Having seen the video, linked upstream, I would PREFER to retrofit a Bosch CP3 style pump, since it eliminates any chance of this particular failure.

How does the later CP4.2 differ from the earlier ones? (<- No, I don't expect you to have the answer, but maybe someone does.)
Bosch went from an asymmetrical cam lobe to a symmetrical cam lobe mid 2020 on the cp4.2 used in the HD trucks. Likely the same.
 

c3k

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Bosch went from an asymmetrical cam lobe to a symmetrical cam lobe mid 2020 on the cp4.2 used in the HD trucks. Likely the same.
I'm no expert, but... :)

The CP4.1 has ".1" to signify a single-piston pump. The CP4.2 has a two-piston pump, hence the ".2". Both of them have the roller-bearing-in-a-cup-against-a-cam design.

From what I can see, both the CP4.1 and the CP4.2 have a two-lobe cam with the lobes 180^ apart.

I'm reading that the rumored fix for the CP4.2 is a keyway so the cup cannot rotate. That will keep the roller bearing oriented correctly on the cam. Aeration (improperly primed or running out of fuel) will still be an issue, but not as much.

I'd still prefer the CP3. ;)
 

djevox

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All cp4 pumps are the same basic design- meaning eccentric, cams, springs, body casting (before variant modifications) are the same. The variants are things like heads positioned different directions and gear vs electrical driven.
 

Brutal_HO

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I'm no expert, but... :)

The CP4.1 has ".1" to signify a single-piston pump. The CP4.2 has a two-piston pump, hence the ".2". Both of them have the roller-bearing-in-a-cup-against-a-cam design.

From what I can see, both the CP4.1 and the CP4.2 have a two-lobe cam with the lobes 180^ apart.

I'm reading that the rumored fix for the CP4.2 is a keyway so the cup cannot rotate. That will keep the roller bearing oriented correctly on the cam. Aeration (improperly primed or running out of fuel) will still be an issue, but not as much.

I'd still prefer the CP3. ;)

I know full well what the pump differences are. I was very much a part of the HD community putting pressure on FCA/Stellantis to recall the CP4.2 in the HD trucks.

The assumption I'm confusing a single piston CP4.1 with a two piston CP4.2 in my statement regarding the cam lobe design is incorrect. FWIW, the CP3.3 is a 3-piston pump.

Asymmetrical vs Symmetrical isn't about 1 vs 2 cam lobes, it's about the offset and lift of those 2 lobes.

The links to the dealer communications letters regarding the identification and design of the old vs new CP4.2 are easily found on sticky threads on HDRAMS. In short, if it has a single LARGE dimple machined in the pump body in addition to the small plant/batch dimples, it's a Symmetrical pump.

Anything you're seeing about a keyway being cut is AFAIK misinformation. If anything, Bosch would make the cylindrical pump piston oval to prevent rotation. Either of those designs has the potential to introduce additional wear. The redesign of the CP4.2 may have reduced the likelihood of failure, but did not eliminate it enough for Stellantis to stick with it. The NHTSA "investigation" may have accelerated their recall on the HD trucks (Y78), but it was already in the works according to insider info.

The only fix for the CP4 debacle is a CP3.
 
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Brutal_HO

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All cp4 pumps are the same basic design- meaning eccentric, cams, springs, body casting (before variant modifications) are the same. The variants are things like heads positioned different directions and gear vs electrical driven.

He's actually right that there are CP4.1 and CP4.2 pumps and those differentiate the number of pistons.

The pumps, regardless of piston count, are just clocked differently and have different manifolds for various applications.
 

djevox

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He's actually right that there are CP4.1 and CP4.2 pumps and those differentiate the number of pistons.

The pumps, regardless of piston count, are just clocked differently and have different manifolds for various applications.
Then I got told the wrong thing last week when I was going through mitchell and talking to someone about it. I have more research to do that’s not google.
 

2021EcoDiesel

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Having seen the video, linked upstream, I would PREFER to retrofit a Bosch CP3 style pump, since it eliminates any chance of this particular failure.

How does the later CP4.2 differ from the earlier ones? (<- No, I don't expect you to have the answer, but maybe someone does.)
So I do know the answer to this one! CP4.1 have only one pumping element, so they've only got one roller and bucket rolling along the internal cam of the injection pump. They are used in smaller lower power motors cause they put out a bit less fuel volume. CP4.2 has two pumping elements, two rollers and buckets rolling on a very aggressive cam. Side by side the 4.1 looks like a dirt bike motor whereas the 4.2 looks like a 90 degree V-Twin engine. As far as the CP3 pumps go, they are built a bit heavier and push out massive amounts of fuel, like for 1,000 horsepower race trucks. They use 3 pumping elements on a less aggressive cam and also don't use a roller on their buckets if memory serves me correct. Like a hydraulic lifter bucket runs on a cam in a hemi.

EDIT: Didn't see it was already explained further up before posting, my apologies if I'm beating a dead horse.
 
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Brutal_HO

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So I do know the answer to this one! CP4.1 have only one pumping element, so they've only got one roller and bucket rolling along the internal cam of the injection pump. They are used in smaller lower power motors cause they put out a bit less fuel volume. CP4.2 has two pumping elements, two rollers and buckets rolling on a very aggressive cam. Side by side the 4.1 looks like a dirt bike motor whereas the 4.2 looks like a 90 degree V-Twin engine. As far as the CP3 pumps go, they are built a bit heavier and push out massive amounts of fuel, like for 1,000 horsepower race trucks. They use 3 pumping elements on a less aggressive cam and also don't use a roller on their buckets if memory serves me correct. Like a hydraulic lifter bucket runs on a cam in a hemi.

EDIT: Didn't see it was already explained further up before posting, my apologies if I'm beating a dead horse.

The CP4.2 design pushed higher PSI than the original CP3.3*. The CP4 pumps cost less to manufacture but are less reliable than the venerable CP3 with its separate fuel supply and cam lubrication chambers. The CP3 is also a cast iron pump body as opposed to the CP4 aluminum body.

*Aftermarket CP3 pumps were either bored over or stroked (more typical). The new CP3.3, designated CP-ISB21S3 for 21+ Cummins applications and CP-ISB19S3 designation for the 19-20 trucks recalled (different clocking and manifold) generate PSI equivalent to the CP4.2. I don't think anyone has done any extensive evaluation yet to determine the difference.

This is a CP4.2 (Asymmetrical) qty and placement of dots do not matter, if there's no LARGE dimple as shown in the other image, it's an older style pump.

1672168834574.png

This is aCP4.2 (Symmetrical) note the LARGE dimple. Smaller plant/batch dimples will be on the lower part of the pump.

1672168810603.png

This is a CP-ISB19S3/CP-ISB21S3/CP3.3)

1672168723818.png
 

2021EcoDiesel

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My dealer and I also get along well, even though I purchased my truck in Toronto, 8 hours south of my home, my guess is that your dealer is hoping a fix will be available by the time your appointment is up. I find that it should not be a hard fix because the trucks built after July 2022 are not affected, you would think, simply put the new components in the affected vehicles.
On the pump repairs, did your dealer simply replace the same pump or did they install the new components of the July 2022 production trucks? I did ask my dealer about the recall and they said not one vehicle came in for pump failures, I realize we are a small town, 45,000 population and maybe another 20,000 with all the surrounding much smaller municipalities, so not that many diesels were sold compared to Toronto and surrounding areas with a population in the millions.
You nailed it, when I spoke to him again yesterday, he said that his department has replaced one failed pump and another that was faulty but didn't fail yet, didn't specify if these vehicles were ecodiesels or cummins motors, both were warranty repairs not recall. However he said FCA/Stellantis hasn't issued a formal fix yet. He also added that he is unsure how many pumps he will be able to order per week, maybe 2-3 he mentioned. But he thinks the fix may be out soon, hopefully before my appointment, he also added that he is unsure if the fix will be just the pump, or if it will be the same pump.
 

Rebelguy2020

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You nailed it, when I spoke to him again yesterday, he said that his department has replaced one failed pump and another that was faulty but didn't fail yet, didn't specify if these vehicles were ecodiesels or cummins motors, both were warranty repairs not recall. However he said FCA/Stellantis hasn't issued a formal fix yet. He also added that he is unsure how many pumps he will be able to order per week, maybe 2-3 he mentioned. But he thinks the fix may be out soon, hopefully before my appointment, he also added that he is unsure if the fix will be just the pump, or if it will be the same pump.
Thanks for the update. Hopefully we will all get the fix soon.
 

Brutal_HO

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My dealer and I also get along well, even though I purchased my truck in Toronto, 8 hours south of my home, my guess is that your dealer is hoping a fix will be available by the time your appointment is up. I find that it should not be a hard fix because the trucks built after July 2022 are not affected, you would think, simply put the new components in the affected vehicles.
On the pump repairs, did your dealer simply replace the same pump or did they install the new components of the July 2022 production trucks? I did ask my dealer about the recall and they said not one vehicle came in for pump failures, I realize we are a small town, 45,000 population and maybe another 20,000 with all the surrounding much smaller municipalities, so not that many diesels were sold compared to Toronto and surrounding areas with a population in the millions.

RebelGuy2020, I'm gonna give him a call sometime this week just to confirm, but from what he told me, the recall is only on the pump, a Bosch CP4.2 (please correct me if I'm wrong.) He didn't say it was a different pump, just one manufactured outside the window of error they have discovered. So I'm thinking it may come direct from Bosch or possibly from the Sterling Heights Ram Truck plant in Michigan.

It would seem that what they are referring to as the "new" pump is the Symmetrical cam lobe version (large dimple) of the "redesigned" CP4.2 as that was the same timeframe they rolled it into the Cummins HD trucks. Thankfully, on the HD's they are going full on CP3.3 retrofit for all the 19-20 models with a CP4.2 regardless of design.

Ford still uses the CP4.2 on the Superdirty's though it's said they spin them slower at lower rail pressure. It's likely that same holds true for the Ecodiesel application.
 

AKDiesel

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For those that have had fuel pump failures, were there any signs of any issue prior to failing? Poor fuel economy, power loss, anything? I'm talking the days leading up to the failure. I know some things may be small and looked over but then looking back after a failure it may make sense. I guessing there were no signs and it just failed but just wanted to ask.
My fuel pump failed on 11 Jan (confirmed by dealership on 25 Jan, which was the first available appointment to get my truck in...smh).

No issues whatsoever prior to the pump failure. Thankfully, it failed while parked and not driving down the road.
I had auto-started my truck. I jumped in and was responding to a text on my phone. The truck then shut off for no apparent reason (i.e. auto-start hadn't timed out). I thought it was kinda weird...so started the truck normally, and about 10 seconds later I got the "Service Electronic Throttle Control" message and the engine shut down again.

My truck had been in for service on 22 June, 2022, and I was put on the list for a fuel pump at that time. According to the dealership, I was #20 on the list when the pump failed - so still ~10 weeks out from getting the recall accomplished.
 

Brutal_HO

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My fuel pump failed on 11 Jan (confirmed by dealership on 25 Jan, which was the first available appointment to get my truck in...smh).

No issues whatsoever prior to the pump failure. Thankfully, it failed while parked and not driving down the road.
I had auto-started my truck. I jumped in and was responding to a text on my phone. The truck then shut off for no apparent reason (i.e. auto-start hadn't timed out). I thought it was kinda weird...so started the truck normally, and about 10 seconds later I got the "Service Electronic Throttle Control" message and the engine shut down again.

My truck had been in for service on 22 June, 2022, and I was put on the list for a fuel pump at that time. According to the dealership, I was #20 on the list when the pump failed - so still ~10 weeks out from getting the recall accomplished.

That's odd that they wouldn't push a failure to the front of the line, it's a completely different parts kit.
 

AKDiesel

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That's odd that they wouldn't push a failure to the front of the line, it's a completely different parts kit.
Sorry for the confusion. They did push me to #1.
I was just trying to relay that even after getting on the list in June, that I was still about 10 weeks out from getting the recall accomplished.

Currently waiting on parts to complete my repair, as the fuel pump disintegrated and contaminated the entire downstream fuel system.
 

Brutal_HO

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Sorry for the confusion. They did push me to #1.
I was just trying to relay that even after getting on the list in June, that I was still about 10 weeks out from getting the recall accomplished.

Currently waiting on parts to complete my repair, as the fuel pump disintegrated and contaminated the entire downstream fuel system.

Roger, I misread.

Also FYI, this thread on 5thgenrams is specifically for a recall related to CP4.2 pumps on the 1500 ecodiesel.

If you're not a member of HDRAMS, you might want to join and post over there for a more relatable experience with us HD guys and recall Y78.
 
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dmitriy

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Sorry for the confusion. They did push me to #1.
I was just trying to relay that even after getting on the list in June, that I was still about 10 weeks out from getting the recall accomplished.

Currently waiting on parts to complete my repair, as the fuel pump disintegrated and contaminated the entire downstream fuel system.
Bummer for your experience so basically in 6 months you were only 10 spots up on the list and now that it actually failed they have to dig in way more into your motor & its going to cost them more for it? I sure hope those replacements come in sooner....
 

Malodave

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I have been using Hot Shots EDT in the Fuel since I got the truck. Hopefully it keeps
the pump from eating itself until they have parts available to replace it. I am also
hoping that it is only a Hardware fix and does not reflash the PCM. I have the GDE tune
that was overflashed the last time it was in for recall and warranty work.

Malodave
 

Brutal_HO

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I have been using Hot Shots EDT in the Fuel since I got the truck. Hopefully it keeps
the pump from eating itself until they have parts available to replace it. I am also
hoping that it is only a Hardware fix and does not reflash the PCM. I have the GDE tune
that was overflashed the last time it was in for recall and warranty work.

Malodave

For the HD trucks, they all receive a PCM flash.

In every case we're aware of, the owner was able to reinstall their tune flash in the parking lot. There was a rumor that some trucks PCM were "locked" like the 2022+ PCM are, but it was brief and seems unfounded.

Be prepared to have to reflash your tune after the dealer work.

ETA: This has pretty much been confirmed as fake news. The tuners were not updating their tunes to use the latest stock PCM flash Part Number so the tune flashes were failing.
ETA2: Found out the issue was a 3rd CRC check was added to the PCM flash files that the tuners hadn't initially figured out .
 
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djevox

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Is anyone thinking about waiting a couple years to get their recall done? The independent business I’m associated with can’t do recall work for stellantis (meaning I’d eat labor) and I don’t trust dealers, especially when multiple local dealers send us their trouble vehicles. IIRC, I have 10 years from purchase date to get any recalls done. The only thing giving me pause is if something grenades, I’ll be given a hard time for not getting it repaired quickly.
 

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