In-Depth Look at the Bosch CP4.2 High-Pressure Fuel Pump

[@mr8610]

If these pumps simply failed at 100,000(ish) miles and it was a simple replacement, a lot of people honestly wouldn't really complain all that much. They'd be annoyed, sure, but a $1200 pump and a Saturday evening sure beats a $10,000 professional fuel system replacement. So happy people like you have developed disaster prevention kits.

[@johnvirgilwilliammccoy2332]

Aside from the plunger rotation. We have found, at the shop I work at. Once the HP is replaced and truck is running again. Testing the fuel pressure of the electric feed pump is often low. Still within spec, but on the low side. We concluded the possibility when the electric pump pressure is low. The cp4 has inadequate lubrication and cooling.

[@dance3476]

Does your bypass kit work or fit the 2021 jeep wranglers cp4 pumps?

[@SSfueled]

The current Gen2.1 version will only fit 2011 to current Ford 6.7 Power Stroke engines. We are working on an EcoDiesel variant and one of our engineers is testing on his personal Jeep Wrangler right now. We should have a final version released this year.

[@PowerStrokeTechTalkwARod]

Thanks Luke, appreciate the great break down for us.

[@IvayloKanazirski]

are there any symptoms or noises before this pump dies?

[@SSfueled]

We noticed an increase in return fuel temperature in the two CP4s we failed in-truck to field test our Disaster Prevention Kit.

[@abrahamrico2978]

How much are good ones worth, I have like 20 cp4 just laying around

[@SSfueled]

We honestly can't say. If they are in good working order, then they should be worth more than a core charge.

[@bavarianfinestmotors]

Veryyyyy informative video! Thank you! Loved you explanation of the fuel flow direction! Absolutely amazing job!

[@harrystamper2665]

Certainly agree there should be no air in the pump. Also, if there was a partial vacuum the fuel would vaporise to fill the space, and that would give rise to flashing and cavitation. What I think is happening is that the plunger 'hangs' back after it has taken the controlled volume of fuel, as the cam follower continues its journey, and picks up again on the plunger on its return journey to compress whatever amount of fuel is sitting above the plunger. This detachment and re-connection therefore causes the light tapping sound and, as higher flow rates are needed by the engine, the cam follower and piston will remain almost in continuous contact during each revolution of the pump rotor. This explains why the tapping is greatest at reduced flowrates and goes quiet when the throttle is opened.

[@catapult182]

Does the cp4 bypass kit void the warranty?

[@Tyani-sz6cg]

Do you have a bypass kit that will work with a 2011 VW Jetta?

[@dinc379]

Is there not been a bypass unit for the duramax yet. Thanks

[@stevearrington7139]

I just purchased a 2020 ram 3500. It has the cp4.2. Is that good or bad? Is it the 4 2 different to combat the issues the cp4 was having? Any info would be greatly appreciated. Thank you or anyone who replies

[@kovacszoltan9196]

Can I use this bypass Kit for a BMW F30 318d with the B47 engine ? Thank you

[@MCMUSICH]

Does it void warranty

[@hockeyman2274]

Would installation of the disaster prevention kit void factory warranty?

[@Tyani-sz6cg]

Can you do a video comparing the CP4 to the CP 4.2?

[@SSfueled]

They are the same. CP4 is a general term for the CP4.1 and CP4.2. The CP4.1 is a single cylinder pump that is used on smaller engines. A CP4.2 is the two-cylinder pump that is used on 11-24 Ford 6.7s, 11-16 GM LMLs, and 19-20 6.7 Cummins. There are differences between the CP4s in the 11-14 and 15-19 models, but they are both CP4.2s. Here's a video that shows displacement and flow differences for various CP4s: kzbin.info/www/bejne/oJ_Nm5yPa9SSr6Msi=TKS3qKZMzESjVg1v

[@mrglock2313]

​@@SSfuelednow that you have come out with the DCR in your testing how long can we expect your pump to last? Should we still run lubricity additive with your pump and does your pump void a Ford warranty? Thanks in advance

[@SSfueled]

@@mrglock2313 we wish we could say it will not void the warranty, but that’s Ford’s decision. We don’t have an exact life cycle time because none have worn out yet. We’re expecting it to last the life of the engine as long as it’s fed clean fuel. In two reported cases, it’s proven to handle water and rust.

[@mrglock2313]

@@SSfueled thanks for your response. I will buy a DCR anyway. If they try to void my warranty for upgrading their crappy part's we will just deal with that when the time comes. I have an appointment with arod in April to get rid of the cp-4. I look forward to having it done. 👍👍

[@SSfueled]

@@mrglock2313 He's one of the best. Thank you!

[@dustinjones5762]

Great video! I was wondering if there was a reason why the piston and roller turns in the bore?

[@dustinjones5762]

Thanks for the info! Again great video!

[@shaun2love]

Dustin jones if we compare Engine camshaft and valve rotation, same situation happening there

[@shaun2love]

Only Difference is instead of Engine valve , roller bearing Rotation

[@MCMUSICH]

What is the difference of the cp3 and 4

[@jimb4090]

Oval piston and bore....no turn.

[@robertjohnsonmetals3727]

How can I tell if I do have a failure with out pull stuff, apart

[@lenhofer3214]

U showed us how that roller rotates and eventually gernades that pump....once its rotated 90 degress will that cause a rise in the pressure, in the pump output...?

[@cjchico]

I have a 13 Powerstroke. The pump was replaced under warranty when in failed in Oct 2016. I did a disaster prevention kit and saw "Bosch 4050" stamped on the back side of the pump. Every pic of a 2011-14 pump I could find shows "Bosch 4000" stamped. Every pic of a 15+ was stamped 4050. Does this mean I have the updated 2015+ pump?

[@colby1109]

is that vcv bypass block available for 2014 powerstroke? if so i cant find it on website.

[@musiclust4me]

Last year I had a CP4 pump failure on my 2015 Duramax Allison 2500 HD Silverado. It happened at 125,800 miles, 800 miles after my extended warranty. I convinced Chevy to help with some costs but I still was out of pocket over $4,000. I asked them if they would convert it to a CP3 since they had to change out everything. They said that in order for Chevy to pay for their portion they had to keep it at stock, this terrible CP4 pump. Now it has a 2 year warranty so I am either going to dump it or convert it. It seems all the new diesels they are still using these terrible pumps and I do not know why. I was reviewing videos and some folks were going from the 4.1 to the 4.2 but I think it would have the same issues, am I understanding this correctly? What is the difference in the two options of the conversion kit with or without a pump? Would a failure still happen if you buy a conversion kit without the pump? (Sorry I am not a mechanic).

[@SSfueled]

Apologies for the late reply. We missed your comment last year. A CP4.1 is a single cylinder CP4 used for smaller engines. The CP4.2 is a two-cylinder pump and is what the light duty trucks use. A CP3 conversion kit without pump is only the kit portion. It allows for someone who already has a CP3 to retrofit it into an LML. Most conversions will require tuning, except for our No Tuning Required complete kit or the 50 State CARB complete kit.

[@bluesteeljay9343]

What about for a 22 ecodiesel JT bypass?

[@josecatalan6314]

Hello, thanks for the information, do you have it written? I am Spanish-speaking and it is very difficult for me to understand in the video.

[@markthompson1134]

how much for a upgrade i am from uk do you sell to uk

[@billbabbs3871]

I have one of your CP4 Bypass Kits, and thinking about installing it on my 2019 F350SD 6.7, would this void my warranty if installed?

[@billbabbs3871]

@@SSfueledThank you

[@carl2591]

@@SSfueled .. you say "in theory" it should not void the warranty but have there been any issues were the bypass kit was installed and a truck was taken to ford under warranty for fuel system issues and what was the outcome.. ??

[@bcbloc02]

What about the CCR1600 pumps?

[@jmolly7614]

what are the cam and bearings made out of?

[@jdillon8360]

Hi! Can you make a video on the Bosch CP2 pump? Do you guys work on those?

[@speterbilt]

Is the cp3 on the 2021 ram diesel now? I'm looking at a 2016 Ram cummings 3500. Do you know which pump it has?

[@speterbilt]

@@SSfueled thank you sir!

[@kylehlacy]

Is there a kit available for the 2020 RAM 2500 6.7 diesel?? Let me know. How can you tell if something has gone bad?

[@kylehlacy]

@@SSfueled thanks!

[@bobbondarul7448]

Nice Any updates on your gen 2 ?

[@SSfueled]

We'll be unveiling a new product at the National Farm Machinery Show on 2/15/2023. Keep an eye on our channel for a video of that next week.

[@jerrywhittaker1052]

I'll buy the gen 2 as soon as it's released! Thanks for making the USA better!

[@jarnokarjalainen2668]

How much does this kit cost? You have one for BMW n57/30d engine, F11 chassis?

[@jarnokarjalainen2668]

@@SSfueled ok, keep us posted.

[@adytssu]

How do I get the air out of the pump? I just removed the sensor from the pump for a check. After mounting it, the engine started and stopped. Maximum pressure reaches 11 bar. Too weak to start. Land Rover Sport 3.0 306DT 2014

[@adytssu]

@@SSfueled After three days of trying all the methods to get the air out of the pump, I bought another high pressure pump. He started immediately. Maybe you can find a way to vent and get a pump up and running again. I think it can be a problem to remove the sensor from the pump. I asked a second-hand parts dealer in the area where I bought the pump, and they told me that they had encountered this phenomenon many times. They tried to repair a pump that caught air but was unsuccessful. Thank you

[@wretchedrider2157]

Is your product tested/available for the 2020+ 6.7 Ford? Much obliged!

[@droopdude11]

I believe spe diesels Kit does

[@AZ33033]

Is there a bypass in the works for 19-20 6.7l cummins?? other than whole cp4 to cp3 conversion

[@chrisdeez2176]

Do you guys have a bypass cover for a Lb7 cp3 to run no lift pump on the back of the pump? so i can not run the mechanical lift pump on the back of a cp3? asking because of a project im doing with a lb7 with triple turbos and i need as much room as i can get, Also would you guys ever be making a 10,12,13mm pump kit for a cp3 that would be a diy kit? like build your own 12mm cp3 kit?

[@gauravgawade7432]

Hi, In our application we don't have electric lift pump on vehicle and totally rely on Fuel pump to pulls fuel from tank and through filters and main problem is even after little clogging of filters pump starts starving for fuel and getting issue to start the engine.

[@MrSuperchargedv8]

what brand is that toolbox?

[@volastod9327]

Does it fail over time or all at once?

[@volastod9327]

@@SSfueled thank you

[@Comfortson_m]

hi,what could be the problem if diesel come from the return have pressure but no diesel to the injectors

[@fs0088]

This video surprises me: I'm from Germany and several million CP4 Diesel cars run here every day without any issues. The problem that caused the roller to spin by 90 degree was resolved by Bosch in 2011 or 2013, i don't remember the exact year. Do you have really issues with CP4's, build after 2013 ?

[@matthewnosal6893]

In 2020 Fords F250’s cp4 pump got alignment screws in the housing for the lifters. 95% of The cp4 failures that I’ve seen are due to def or water contamination. The evidence is rust. The failures with no rust are most likely due to accidental gasoline. No lubricity at all. Once the cam and roller are scared, it’s just a matter of time before things get nasty.

[@mikehub6664]

Our pump failures after 2013 is cause by fuel grade difference in the USA Ultra Low Sulfur fuel not providing enough lubricity for the CP4 pump. CP4 was designed and tested in Euro grade diesel which has a higher lubricity. As Matthew stated before fuel quality also varies here and also increases risk of wear and potential damage. Realistically in the new common rail diesel engines should have a secondary inline Filtration system for water sediment and rust. After market system in Australia seem to have it down.

[@Oockeshoek]

My 2017 CP4 pump failed (BMW B47 20d 190hp engine). It has a guide pin to prevent rotation, but still failed. The roller was eaten up by the cam at 245.000km. Repair was €5662.

[@waynemeredith4287]

Great information 👍. Seems it should be possible to design a roller system that won’t rotate and destroy the pump! Another thought. With disaster kit installed. When pump fails debris is sent back to your tank. Why not install a filter there to catch the debris for it can get that far?

[@jimb4090]

Oval bucket and bore....

[@jimb4090]

SPE has that covered....

[@duconce]

The tank has a large filter system, doesn't that clear that problem, the injectors is the problem

[@richardkeyes986]

I'm just waiting on my DCR hearing June.

[@SSfueled]

Thank you for your business and patience. June is our target, but we do not want to rush it. We're going to make sure that it is thoroughly validated and refined before release into the market. We appreciate your trust.

[@Rift45]

Has Bosch not yet redesigned the pump to fix this? It’s been a long time. Or is 30,000 psi impossible to run reliably?

[@Rift45]

@@SSfueled Glad to hear it! That may be the way to go for a new truck then. Thanks!

[@johnmazza9432]

It's a little difficult for me to see exactly what you are referring to as you want us through this. Will you be at any tradeshows in the near future or are there any dealers who can show your devise in person ? Also, I'm imagine that adding a lubricant to the fuel is a good idea. Anything you recommend ? How about 2 cycle engine oil ? If so , how much ?

[@johnmazza9432]

@@SSfueled I spoke with a diesel mechanic this morning who said that the lifters have guides that are suppose to keep them aligned but that when the guides break, they will spin as you suggest. Does your re-routing of fuel result in any lose of pressure or volume ? And do you put a filter on the fuel being sent back to the tank ? Is it possible to simply put a filter between the pump and the injectors ? In stock form, does the fuel returning to the tank get routed back through a filter ?

[@ryantessaro9927]

Would it be ideal to replace this pump say around 150,000 miles or are these failures not really prone to wear and tear as far as mileage but to just fuel contamination? Just curious coming up on 150,000 miles on my truck and $1100 now to replace it seems better than letting it ride if wear is a factor

[@ryantessaro9927]

@@SSfueled thanks for the response I’ll definitely make sure to wait to see what you guys come up with in 2021 👍

[@CryptoPivot]

Would sure like to see answer to this.

[@jimb4090]

The pump is still a shit design. It's not just failing at 150k, I've seen some in warranty as well. Until the friggin bucket and roler stays aligned, nothing changes. Oval would be nice.....

[@richardbrown5045]

I supposedly have the newer design symmetrical cp4 pump and curious if they did in fact fix it although I doubt it since 2021 seem to have gone to a cp3 pump

[@jimb4090]

My guess is...no. Coatings don't do squat for a bucket that can turn 90°. Unless and until the bucket and bore go slightly oval to prevent the misalignment nothing changes.

[@LoyaltyClips]

Thanks for the info 🤙🤙

[@larrythompson8630]

If the bucket? Rotates because no anchor. Huge defect. Should be warranted even after normal miles. Defect. So your unit does NOT protect the bucket rotation? Just should reduce chance of metal shavings into engine? The problem, defect not corrected?

[@bryontharp5790]

Why can't they pin the barrel so it don't spin with the roller

[@SSfueled]

That's a great idea and one that has already been implemented. Later variants of the CP4 do have a guide. It does help with one type of failure, but doesn't eliminate the other.

[@pulvermacher80]

So glad I waited for the 2021 ram 3500 model!

[@MCMUSICH]

What are they doing on that from 2020

[@robinali2857]

True, although the 2021's with diesel engines can spontaneously combust lol

[@TinManOne9]

They made those look like they were marketing for the " Paw Paw" that , surprisingly, had a great 401k after the '08 crash - I get that most rant over the vertical screen, yet you can install that on anything, and your truck doesn't scream " I'm 67, just bought an 18' Jayco , and I have no experience backing into anything", but " the seats are better than my lazyboy, and I can watch Wheel of Fortune without my glasses on at the Loves parking lot, they even have ladies that come by to ask if you need anything, and they're so friendly"

[@harrystamper2665]

Do you ever see any evidence of flashing/cavitation when these pumps operate at low rates i.e. when inlet throttle valve restriction is greatest? My Macan has a knock at low throttle openings but is quiet when power applied. Thanks

[@jfordman69]

Is there a kit available for the Titan XD 5.0 diesel??

[@jfordman69]

@@SSfueled awesome looking forward to it.

[@TheMongoose87]

Definitely needed for the Titan XD 5.0 please!

[@heyttsguy]

Would be great if you guys could do a video on Ram's CP4.2 Asymmetrical(2019) vs CP4.2 Symmetrical(the 2020 revision) pump design and if the newer design solved any failure issues. If the bucket is prone to rotating, to me the obvious solution would be for Bosch to incorporate a keyway into the design. Word is that Ram went back to the CP3 for 2021.

[@heyttsguy]

@@SSfueled 2020 Ram owners with the Symmetrical CP4.2 are hoping the reliabiltiy issue was rectified. There doesn't seem to be any issues with those YET. Fingers crossed.

[@resharddurdley6987]

@@heyttsguy does the 2021 6.7 Ford powerstroke use the same system? I just ordered a Ford 21 6.7 Tremor F-350

[@luispadula6209]

@@heyttsguy would the 2020 ram Eco Diesel engine have the new design 4.2

[@jimb4090]

Alternatively...why a round bucket? Why not oval? CNC would make the crankcase and bucket change a trivial matter in production. I suspect Bosch doesn't give a damn except for a lowest cost of manufacturing and that would be a round part....

[@Oockeshoek]

I have disassembled my CP4 pump for BMW 2.0 B47 diesel engine, it actually has slot in the piston with a holder inside it.

[@StreamMastersPW]

curious to see if anyone has tore down the revised upgraded pump.

[@StreamMastersPW]

@@SSfueled any videos we could see or find ?

[@charlietuna5962]

@@SSfueled So in an earlier comment, you state a 2015 ¾ ton D'max would have had a CP4.2 installed? I've got a 15 Dually. Is there anything to worry about with the 4.2 version? I've been looking at your site, and do not find any "bypass block", only some $2,000 CP3 conversion kits? Is that block not a separate part available to us? And could an Exergy System Saver Regulator be used to potentially provide additional safety measures? I'm still making payments on the truck, and really can't afford to pay for a $2,ooo pump plus installation, so looking for a cheaper alternative for now. Thank you kindly for this informative video, and any feedback you can provide.

[@charlietuna5962]

@@SSfueled Thanks for the prompt response. And I'd seen in another of your videos, 4.2 just means 2 pistons, so it isn't the v2 I was expecting. Thank you very much

[@ox-cetane4887]

Has anybody ever provided with a definition for diesel fuel lubricity beyond just the words? what is the causal mechanism for poor diesel fuel lubricity?

[@SSfueled]

Good question. Our specialty is the mechanical aspects of diesel injection, not the chemistry. That would likely be in your wheelhouse. Wear scar is typically how lubricity is measured, and @hotshotssecret may have done a diesel fuel comparison.

[@hughparker3971]

It seems the obvious fix is the roller cam alignment. Who has a solution for the issue with that?

[@jameskelly9510]

Can you rebuild BMW one?

[@jameskelly9510]

@@SSfueled any recommendations?

[@hotshottransport945]

How long b4 these cp4 start failing? I know ppl have diff mileages. But “most people” about how many miles does it last?

[@johndoe-im9fr]

pretty early for a lot of people i've seen. a lot before 30k miles.... it's really bad.

[@highball7347]

@@johndoe-im9fr I think the internet makes it seem bad. The 6.7 super duty is a very popular engine and how often do you hear about it?

[@AdventureMan-kx3dr]

Mine failed at 72,000 or 5 months of use and took out everything out. I actually prefer the Denso HP4 set up

[@greggapowell67]

Just purchased the gen2. Thanks.

[@richardjones3112]

Great video.Well explained.

[@conniechapin9278]

It looks to me like the true problem is the roller lifter rotating in the housing. How about a square lifter, and something that fits between the housing and head that guides the square lifter. Maybe with a Teflon type of coating, as I suspect that the steel lifter riding against the aluminum housing is a contributing factor of the original failure.

[@jimb4090]

Oval....

[@brisonpalmer6730]

What pump do I have on my 2014 Ram Cummins and how do I protect it from this type of damage?

[@ritzcake86]

You have a CP3

[@brisonpalmer6730]

@@ritzcake86 thanks

[@doc_d4566]

So glad Ram went back to the CP3 in 2021. Bosch needs to be sued for a few hundred million dollars.

[@petersannicolas8949]

CP4 garbage should have stayed with the CP3 lots of people having trouble with their new trucks now

[@jeramiebentley4054]

Its always something

[@ovi1990]

Market economy at its finest!

[@joelmartin2826]

Any chance I could use your product on a VW TDI with a single cylinder CP4? I must do as much preventative maintenance on that system as possible-seeing as how VW grenaded TDI distribution in America because of their utterly naïve so-called #Dieselgate debacle (idiots). Although I’d love to purchase your product, even if I have do a little modification-because that’s the only weak point in that amazing motor of theirs-still seeing wide and far distribution in Europe, Asia and South America (you know-places & economies we’re suppose to genuflect to as better than our own, according a few charlatans out there misdirecting certain research-but that’s another story)

[@joelmartin2826]

@@SSfueled: Great news! Although I’d be lying if I said there isn’t a burgeoning demand for such a device-perhaps even outside the US! I’m certainly willing to be involved in any “beta-testing” trials, for what it’s worth. In the meantime, for anybody else needing a forthcoming S&S Diesel TDI CP4 Disaster Prevention Kit--make sure you have at least a 3 micron Donaldson or CAT fuel filter in line on your fuel system--as well as a decent fuel lubricity additive with EVERY tank!!! (I use Opti-Lube XL for fuel lubricity specifically. But there’s other decent additives like Amsoil, Stanadyne, Hot Shot Secrets and Liqui Moly to name a few)

[@danielbarros8136]

También necesito un kit de prevención para mi vw Tdi. I’ll be waiting for it to come out.

[@tombentley887]

Why doesn’t someone take the cp4 pump have 2 rods instead of one to help the piston not be able to turn. In the piston do holes for the rods that will help to stabilize the turning of the piston. The pistons being able to turn like that is a mentally unstable design.

[@SSfueled]

Great idea. Later revisions of the CP4.2 have this feature. It seems to help with one type of failure mode (bucket turning sideways), but not the other (roller seizing). The CP4s in 2019-2020 Cummins have this feature and it did not seem to reduce the failures enough for Cummins to continue using them.

[@tuvshinkhantaishir3910]

My pump broke last night. This pump is garbage.

[@MrOmar7006]

La peggiore pompa del mondo! #bosch #cp4

[@johnstinson4026]

I have a 2019 ford 6.7 diesel Literally 2000 milles. Truck sat around here n there. One day it ran rough told me to regenerate but it started cutting off so I couldn't. Then I pulled exhaust dog filter and company baked it n removed black soot. Then multiple injector codes....injector performance trouble code and short high side injector codes. Truck will not start. I'm thinking cp4 pump failure. What do y'all think about this ?