2020 Ram 2500 CP 4 Failure

tjfdesmo · May 20, 2020

There is a fuel control actuator, or "volume control", so to speak, on the pump. This is the first place to look for evidence of debris from a pump failure. It will collect on the screen. Yes, the rail stays pressurized, but rail pressure varies with speed/load, etc. Return fuel bleeds back to the tank. I see no way for this to ever cause a failure.

Harold Barnes · May 20, 2020

tjfdesmo said:
There is a fuel control actuator, or "volume control", so to speak, on the pump. This is the first place to look for evidence of debris from a pump failure. It will collect on the screen. Yes, the rail stays pressurized, but rail pressure varies with speed/load, etc. Return fuel bleeds back to the tank. I see no way for this to ever cause a failure.

So if the pump is always pumping 29k psi there is a bleed valve to bleed off pressure?

tjfdesmo · May 20, 2020

Harold Barnes said:
So if the pump is always pumping 29k psi there is a bleed valve to bleed off pressure?

The rail pressure is varied according to demand, and there is a rail relief valve to prevent over-pressure. The return port is before the high pressure side.

Harold Barnes · May 20, 2020

tjfdesmo said:
How could you have cavitation when Ram uses a lift pump to push the fuel to the CP4, and if the filters were not causing undue restriction? Exhaust brake has nothing to do with it. Cummins supplied the engines to Ram, but Ram is who warantees it. This story does not add up.

How could I h

tjfdesmo said:
How could you have cavitation when Ram uses a lift pump to push the fuel to the CP4, and if the filters were not causing undue restriction? Exhaust brake has nothing to do with it. Cummins supplied the engines to Ram, but Ram is who warantees it. This story does not add up.

All I know is what I am told. Frankly I don’t care who pays for it or what caused it. I just want it fixed with out me footing the bill.

tjfdesmo said:
Someone who I consider trustworthy, with direct access at FCA, has said that the parts draw rate of CP4s is nearly zero, so that's why separating the wheat from the chaff is important. I could create a bookface account and say mine blew up, but it wouldn't make it so.

Harold Barnes · May 20, 2020

Last Thursday morning. Saw the metal my self yesterday.

tjfdesmo · May 20, 2020

There's a photo none of us want to see our truck in. Please post updates as you go.

chri5k · May 20, 2020

Here is a study of diesel additives and their ability to improve lubricity.

https://www.jatonkam35s.com/DeuceTechnicalManuals/Diesel_fuel_additive_test.pdf

Harold Barnes · May 20, 2020

tjfdesmo said:
There's a photo none of us want to see our truck in. Please post updates as you go.

May go this route so I don’t have to worry about it. Sooner or latter it will happen out of warranty.

tjfdesmo · May 20, 2020

I'd get some miles on it in stock form after the warranty work to be certain they don't miss anything downstream, before going down that path. Once you do that you kiss your warranty goodbye.

JS4024 · May 25, 2020

So because your 1 in 10,000 unit failed on a RAM you are “rethinking” your RAM purchase? When the power joke and the duracrap engines use the same pump??? Laughable. Endurance wise the Cummins is the finest motor out of any of the big 3 engines in pickups. The other manufacturers lie when they say this engine was built from the bottom up as a diesel. Cummins is the only one that does that and to get all freaky over a fuel pump failure is kinda rediculous. This is Bosch’s issue as they manufacture the pump and it’s known that it was not spec’d for US fuel, or... for that matter Euro fuel as they have the same issues over there.... Get them to throw in new plumbing and injectors to make sure all is well....

Harold Barnes · May 25, 2020

JS4024 said:
So because your 1 in 10,000 unit failed on a RAM you are “rethinking” your RAM purchase? When the power joke and the duracrap engines use the same pump??? Laughable. Endurance wise the Cummins is the finest motor out of any of the big 3 engines in pickups. The other manufacturers lie when they say this engine was built from the bottom up as a diesel. Cummins is the only one that does that and to get all freaky over a fuel pump failure is kinda rediculous. This is Bosch’s issue as they manufacture the pump and it’s known that it was not spec’d for US fuel, or... for that matter Euro fuel as they have the same issues over there.... Get them to throw in new plumbing and injectors to make sure all is well....

They are replacing the whole furl system. I don’t doubt the quality of Cummins. I just wish they would have stuck with CP3 they were using on the 18 and older. At least when the CP3 dies it doesn’t crap metal through out the fuel system. I love the truck but I need to be able to depend on it.... All of it.

Yukonbill · May 25, 2020

So for use uninformed types, what does CP4 stand for? Is that a code that when PCM is checked it’s a. Ode?

lastly, What is TDR? Warranty company?

Regcabguy · May 25, 2020

Harold Barnes said:
I am not even sure they are going to cover it. I know with the Ford and GMC lawsuits manufacturers tried to blame it on the fuel. Both Ford and GMC both changed brand of injector pumps to stop the failures. I know this makes metal but I’m wondering if the metal makes it into the engine.

You've got triple filtration. It's Bosch's fault and they should cover Dodge replacing it. It's a known issue.

Regcabguy · May 25, 2020

Yukonbill said:
So for use uninformed types, what does CP4 stand for? Is that a code that when PCM is checked it’s a. Ode?

lastly, What is TDR? Warranty company?

Turbo Diesel Register

Regcabguy · May 25, 2020

chri5k said:
If they give you a hard time, these guys are working a class action suit on the CP4 for breach of warranty.

https://www.forthepeople.com/class-action-lawyers/cp4-pump-failure-lawsuit/

PS. The failures seem to be lubrication related. the pump relies on the fuel for lubrication. Might want to think about using something like Diesel Kleen to increase the lubricity of the fuel once you get the pump replaced. Not a guarantee against future failures but it does improve the fuel lubricity.

The CP3's go hundreds of thousands of miles with stock fuel. It's the new pump.

chri5k · May 25, 2020

Agree. The design of the new pump seems to need greater lubricity than the current diesel fuel can supply in a large number of cases. Both Ford and GM had issues with the CP4 pump. What I was trying to tell the OP is that when he gats the truck back adding a lubricity improver to the fuel may help over come the shortcomings of the CP4 pump. Either that or get one of the CP3 conversion kits.

leroys73 · May 25, 2020

chri5k said:
If they give you a hard time, these guys are working a class action suit on the CP4 for breach of warranty.

https://www.forthepeople.com/class-action-lawyers/cp4-pump-failure-lawsuit/

PS. The failures seem to be lubrication related. the pump relies on the fuel for lubrication. Might want to think about using something like Diesel Kleen to increase the lubricity of the fuel once you get the pump replaced. Not a guarantee against future failures but it does improve the fuel lubricity.

Most of the time in class action suit only the lawyers come out ahead.

chri5k · May 25, 2020

True for most class actions. However, in breach of warranty cases, the plaintiffs usually gets their issue covered under warranty. In the case of a CP4 failure that can mean $10K worth of work is covered or the plaintiff reimbursed if they were denied warranty coverage and paid out of pocket to fix the issue. The lawyers also get a hefty sum since payment of their fees are negotiated as part of the settlement as representatives of the class.

Harold Barnes · May 26, 2020

tjfdesmo · May 26, 2020

That video, to me, clearly illustrates how much more stout the CP3 design is in every way, especially the bottom end. Cummins and Ram should be ashamed to have gone to the CP4. I just DO NOT buy into the "we needed it for higher rail pressure" BS. The CP4 is lighter weight, and is cheaper to manufacture, and that is why we are saddled with it.

2020 Ram 2500 CP 4 Failure

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