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CP3 Recommendations

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CEL PO 299 Low Boost Puzzle

Diagnose this truck

Within the next year or so I should probably replace the CP3 pump. The truck is all OE aside from BBI Stage 0.1 injectors.

Has anyone put a lot of miles on anything other than a new Bosch pump? The new Bosch pumps are hard to find at the moment. Although I'm fine with a new Bosch CP3 if I can get one, if that's the best decision.

Thanks for any help.
 
The HP pump is just that, a pump. It’s not an injection pump in the traditional sense. All it does is take low pressure fuel and increase it to the very high pressure required for a CR fuel system. They rarely fail.
 
Also the minimum pressure required to fire up is much lower then anything that is on with the engine running.
Doesn't mean it can't be an issue. I remember my first IVECO CDI now 24 years ago that had several HPP fail on me. Back then i wasn't able to start it with the starter anymore but jump starting worked just fine.
I little more rpm during the start sequence covered the problem.
 
Within the next year or so I should probably replace the CP3 pump. The truck is all OE aside from BBI Stage 0.1 injectors.

Has anyone put a lot of miles on anything other than a new Bosch pump? The new Bosch pumps are hard to find at the moment. Although I'm fine with a new Bosch CP3 if I can get one, if that's the best decision.

Thanks for any help.

When I replaced mine I used an S&S Super Sport CP3, nearly stock replacement, new unit. It was priced a little lower than a stock new unit from a lot of dealers / Bosch.

Its pretty pricy to replace a CP3 for a long crank issue, small stuff first would be my recommendation: FCA, rail pressure valve, filters, etc.
 
Thanks, guys.

@Darkbloodmon : The filter was replaced not that long ago. I tested the rail pressure valve (high pressure blowoff, I think) according to the service manual and it passed. There may be an issue with the FCA. I replaced it with a new Bosch FCA after the injectors had been changed since the cranking time remained higher than normal. Changing the FCA brought about strange behavior. I don't remember the details about that (I should keep better records). So I put the old FCA back on which restored normal operation. It might make sense to put that new FCA on again to see how that works out.
 
Thanks, guys.

@Darkbloodmon : The filter was replaced not that long ago. I tested the rail pressure valve (high pressure blowoff, I think) according to the service manual and it passed. There may be an issue with the FCA. I replaced it with a new Bosch FCA after the injectors had been changed since the cranking time remained higher than normal. Changing the FCA brought about strange behavior. I don't remember the details about that (I should keep better records). So I put the old FCA back on which restored normal operation. It might make sense to put that new FCA on again to see how that works out.

Longer crank times could be electrical in nature as well, battery, cables, starter. From memory I believe the FSM spec for engine crank/turn over time is 4 secs and I want to say (scratching my head) the rail pressure needed to turn over needs to meet or exceed 5K psi.

If you have gauges you can narrow it down on the fuel system, assuming the electrical is 100%

A quick and dirty way to test the FCA(old FCA) in terms of pressure for cranking is to observe the crank times with it plugged in, then un-plug it (this will allow the pump to deliver max pressure to the rail). Short spikes to max pressure won't hurt anything, just don't leave it idling like that.

Also check at your local Ram/Dodge dealer to have your ECU flashed to the latest DRB3 updates, I still had a hanging idle issue after replacing my injectors and FCA until the ECU "Recognized" the change according to the tech. The DRB3 Diag/update tool is becoming an endangered species rapidly and I encourage owners of these early 2000s trucks to get those updates before the DRB3 is lost. My local dealer only had one tool (Hendricks Automotive Group) and it was barely hanging on after multiple attempts to flash/update my ECU
 
Also check at your local Ram/Dodge dealer to have your ECU flashed to the latest DRB3 updates, I still had a hanging idle issue after replacing my injectors and FCA until the ECU "Recognized" the change according to the tech. The DRB3 Diag/update tool is becoming an endangered species rapidly and I encourage owners of these early 2000s trucks to get those updates before the DRB3 is lost. My local dealer only had one tool (Hendricks Automotive Group) and it was barely hanging on after multiple attempts to flash/update my ECU

What are the advantages and disadvantages of having the latest ECU flashes done on a 5.9 truck? I've never had one done. In these big government and environmental extremist times, I worry they may slip some eco-tuning into the truck that isn't good, such as they are doing on the new stuff.
 
What are the advantages and disadvantages of having the latest ECU flashes done on a 5.9 truck? I've never had one done. In these big government and environmental extremist times, I worry they may slip some eco-tuning into the truck that isn't good, such as they are doing on the new stuff.

If you get a Smarty Jr it will included the latest update for the truck.
 
What are the advantages and disadvantages of having the latest ECU flashes done on a 5.9 truck? I've never had one done. In these big government and environmental extremist times, I worry they may slip some eco-tuning into the truck that isn't good, such as they are doing on the new stuff.

Doubt it the software system is near obsolete for the DRB3 unit, its been mostly phased out and the vehicles still able to interface with it are few and far between or not long for the road. If they have time to write new software/programing for the unit, they'd still be making new/updated versions of the DRB3.
 
Id advise against it...Probably the best thing you'll get if you update is that the ECM is that the horn is going to start honking if you back up without your seatbelt on...or something like that.;)
 
The injectors were replaced and longer than normal cranking times continue. Around 200k miles.
Have you replaced the lift pump? or installed the Mopar in tank pump conversion kit? Everything I read and have been told is that a failed or failing original type lift pump will cause either a failure to start or a lot of cranking before it starts. I installed the Mopar in tank pump conversion kit as that pump will run cooler and is much more reliable than the original lift pump. Mopar 6800 3870AB, Electric Fuel Pump. Its a fairly easy conversion (aside from pulling the bed to get to the tank, much easier than dropping the tank) as the wiring from the LH front wheel well area back to the tank is already in place (same harness as gasoline models).

amazon.com/gp/product/B0040HSARE


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The conversion calls for using DRB3 to change the model of the engine (due to deletion of the on filter lift pump) but its not necessary to the function of the pump. Everyone above is spouting, "get DRB3 updates done..... yada yada" and the two dealers I located that have a DRB3 unit both told me that the cable was bad and could not get a new cable, and were not interested in repairing it. One dealer is about 30 miles away and the other is about 75 miles away. They both said they didn't know of anyone who had a working DRB3 system. Wished someone would just give me one, I think i could fix the cable.

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Chrysler closed some several hundred dealerships during the 2008 economic downturn and new dealers who have started up since then didn't bother to obtain a DRB3 and the ones with them have apparently failed to maintain the units. As a side note, during the dealership closure, Chrysler closed every single WOMAN owned dealership, even though, in some cases (Michigan for example) the woman owned dealership was the largest selling one in the state, and was closed in favor of a nearby, much lower selling dealership.

Charles
 
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Have you replaced the lift pump? or installed the Mopar in tank pump conversion kit? Everything I read and have been told is that a failed or failing original type lift pump will cause either a failure to start or a lot of cranking before it starts. I installed the Mopar in tank pump conversion kit as that pump will run cooler and is much more reliable than the original lift pump. Mopar 6800 3870AB, Electric Fuel Pump. Its a fairly easy conversion (aside from pulling the bed to get to the tank, much easier than dropping the tank) as the wiring from the LH front wheel well area back to the tank is already in place (same harness as gasoline models).

amazon.com/gp/product/B0040HSARE


#ad


The conversion calls for using DRB3 to change the model of the engine (due to deletion of the on filter lift pump) but its not necessary to the function of the pump. Everyone above is spouting, "get DRB3 updates done..... yada yada" and the two dealers I located that have a DRB3 unit both told me that the cable was bad and could not get a new cable, and were not interested in repairing it. One dealer is about 30 miles away and the other is about 75 miles away. They both said they didn't know of anyone who had a working DRB3 system. Wished someone would just give me one, I think i could fix the cable.

#ad


Chrysler closed some several hundred dealerships during the 2008 economic downturn and new dealers who have started up since then didn't bother to obtain a DRB3 and the ones with them have apparently failed to maintain the units. As a side note, during the dealership closure, Chrysler closed every single WOMAN owned dealership, even though, in some cases (Michigan for example) the woman owned dealership was the largest selling one in the state, and was closed in favor of a nearby, much lower selling dealership.

Charles

@CharlesinGA :
Thanks for sharing your ideas.

The lift pump was replaced not that long ago. I can hear it run when I turn the key to the on position. It still has the external pump.

If you can get the file(s) needed for the ECM update, Controller Technologies rents the DRB3 and a DRB3 emulator.
https://controllertech.com/products/drb-iii-rental

A shop that has a J2534 reprogrammer (they might call it a scanner) may be able to install the ECM update. Ideal would be to find a shop who has successfully performed an update on a truck very much like yours. Not sure how they would get the files needed to perform the update.

I'm not intending to incline you towards having the ECM update installed. I don't know anything about it.
 
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