Ram Heavy Duty Forum

Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

CP4 to CP-ISB21S3 (revised CP3) change for 2021 6.7L Diesel Trucks -- Merged Threads

H3LZSN1P3R

You're doing it wrong
Joined
May 29, 2020
Messages
9,016
Reaction score
8,125
Sooooooo the way I read this. If you have a 2019/2020 truck, the only way you’re getting this new cp3 is only if: your fuel system throws a code, your pump fails, or if they find metal shavings on the pump inlet filter screen. Otherwise, congrats, you’re keeping your CP4. Disappointing.

Hope I’m wrong, or I’ll be unloading this truck before it’s out of warranty. I’m not risking footing the bill for repair later.


Sent from my iPhone using Tapatalk
There is a recall so they all will be replaced i think this info is just for if the pump fails before the recall is completed
 

Mike_SE

Member
Joined
May 27, 2020
Messages
23
Reaction score
30
I believe the tests are to be sure there are no shavings in the system to damage the new CP3.3 pump. Why leave the bomb on the truck even if it hasn't gone off. Interesting they are using the aftermarket designed kits to fix this which is what I thought would be the easiest way out.
 

MEGA HO

Well-Known Member
Joined
Jul 20, 2020
Messages
1,022
Reaction score
1,418
Location
Alberta
I'm just glad I didn't waste money on the aftermarket and was being patient. Not in a hurry to complete this recall as my truck is parked for the winter and I'm away for work until Summer anyways. Hoping the rush will be over by then and I could get mine done without delays.
 

RVTRKN

Well-Known Member
Joined
Apr 4, 2020
Messages
421
Reaction score
276
Sooooooo the way I read this. If you have a 2019/2020 truck, the only way you’re getting this new cp3 is only if: your fuel system throws a code, your pump fails, or if they find metal shavings on the pump inlet filter screen. Otherwise, congrats, you’re keeping your CP4. Disappointing.

Hope I’m wrong, or I’ll be unloading this truck before it’s out of warranty. I’m not risking footing the bill for repair later.


Sent from my iPhone using Tapatalk
Its a Recall, so its going to be replaced, however if the effected VIN (all 2019 -2020) is still running OK, it'll be on a lower priority. They have the kits now, but not enough to just arbitrarily start replacing them. If it fails FCA will be obligated to replace it with the new kit, the cost alone to put in a CP4.2, then pay again after failure, would not make any since. The kit is more likely in short supply like most everything.

I went through the same issue with a recall for the alternator on my 07. It was replaced when my service writer contacted me to set up appointment.
 

H3LZSN1P3R

You're doing it wrong
Joined
May 29, 2020
Messages
9,016
Reaction score
8,125
Yay looks like i have 6 injector codes and a fuel pressure code when truck would not start this morning…… when i get back from work ill try it again but it would seem its time for the cp3.3 from what i can tell by the codes and last filter change there was some shiny sparkles ontop of the filter. Only 3 or 4 of them but they were there lol…..
 

RVTRKN

Well-Known Member
Joined
Apr 4, 2020
Messages
421
Reaction score
276
I would not try to start it, have it flat bedded to dealer. The issue can eat engines.
 

H3LZSN1P3R

You're doing it wrong
Joined
May 29, 2020
Messages
9,016
Reaction score
8,125
I would not try to start it, have it flat bedded to dealer. The issue can eat engines.
There is no way it can “eat engines” really with the tiny injector holes anything that comes out would be hard pressed to do any damage but anyway after 30 mins of trying to start it i left it and called for a ride then just as my ride was showing up i tried one last time and it started no more codes so it was just a fluke it is -38°C out, it was plugged in but it has had no issue in colder temps so it is just strange had no issue on the drive to work…. I must say i an really impressed with how the batteries are in the truck its been almost 2 years with it running a plow and they still crank great even after 30mins of cranking in brutal cold weather….
 

flan

Well-Known Member
Joined
Aug 16, 2019
Messages
3,330
Reaction score
6,487
I wonder if you got a little slug of wax in the fuel line temporarily blocking fuel coming in from the in tank pump?
 

72guy

Member
Joined
Oct 14, 2019
Messages
35
Reaction score
23
Which filter had metal in it? Guess it doesn’t really matter because there should be no, not even 3 or 4, “ shiny sparkles “ in either of the fuel filters. You might pull the fuel regulator, or whatever Cummins/RAM calls it, and check the filter/screen. It sounds to me like you might be a good candidate to have your entire fuel system replaced along with the 3.3. At least that’s what I would want knowing that I had metal in my fuel system. RAM probably feels the same way. Why throw a new pump on a contaminated system and risk a future failure.
 

bigcitymike

Member
Joined
Feb 7, 2020
Messages
65
Reaction score
40
I wonder if you got a little slug of wax in the fuel line temporarily blocking fuel coming in from the in tank pump?
Which if the case, he's probably starved the fuel pump, potentially burning up the delicate bits of the CP4.
 

bigcitymike

Member
Joined
Feb 7, 2020
Messages
65
Reaction score
40
There is no way it can “eat engines” really with the tiny injector holes anything that comes out would be hard pressed to do any damage but anyway after 30 mins of trying to start it i left it and called for a ride then just as my ride was showing up i tried one last time and it started no more codes so it was just a fluke it is -38°C out, it was plugged in but it has had no issue in colder temps so it is just strange had no issue on the drive to work…. I must say i an really impressed with how the batteries are in the truck its been almost 2 years with it running a plow and they still crank great even after 30mins of cranking in brutal cold weather….
If it's -38°C outside, that God's way of telling you to stay inside.
 

flan

Well-Known Member
Joined
Aug 16, 2019
Messages
3,330
Reaction score
6,487
Which filter had metal in it? Guess it doesn’t really matter because there should be no, not even 3 or 4, “ shiny sparkles “ in either of the fuel filters. You might pull the fuel regulator, or whatever Cummins/RAM calls it, and check the filter/screen. It sounds to me like you might be a good candidate to have your entire fuel system replaced along with the 3.3. At least that’s what I would want knowing that I had metal in my fuel system. RAM probably feels the same way. Why throw a new pump on a contaminated system and risk a future failure.
I’ve had debris in just about all my trucks fuel filters over the years. Only noticeable when the truck has a color contrasting black fuel filter housing like ours. I’ve seen some in black plastic fuel tanks I’ve dropped outta the truck over the years too. If you have a spin on canister filter obviously you won’t see any, but from my old 12 valve cummins pre heater filter, 6.0 Powerstroke HFCM and now my rear filter housing on the ‘19 it’s nothing new to me, just the filter housing doing its job. More than likely it’s debris from the filling station either in their tanks or shavings from their pumps.
 

H3LZSN1P3R

You're doing it wrong
Joined
May 29, 2020
Messages
9,016
Reaction score
8,125
Checked stored codes it gave me a cold start fuel pressure to high which makes me believe the fuel was just a little thick and the fuel heater did its job the IP is running at peak performance looking at rail pressure vs commanded rail pressure, im leaving it in the shop for 36ish hours while im on a road trip with a buddy of mine if nothing it will atleast melt the defcicle lol
 

ironmike

Active Member
Joined
Nov 15, 2020
Messages
154
Reaction score
132
Location
Bakersfield , CA
Confirmed yesterday by diesel tech actually working on my 3500 that it is the new recall replacement fuel pump. Not the old / new interim replacement CP4. All parts are in and should be complete next week.
Hopefully the new computer program flash will help with Mpg as I was getting 10-12mpg prior to pump fail...
 
Last edited:

H3LZSN1P3R

You're doing it wrong
Joined
May 29, 2020
Messages
9,016
Reaction score
8,125
I’ve had debris in just about all my trucks fuel filters over the years. Only noticeable when the truck has a color contrasting black fuel filter housing like ours. I’ve seen some in black plastic fuel tanks I’ve dropped outta the truck over the years too. If you have a spin on canister filter obviously you won’t see any, but from my old 12 valve cummins pre heater filter, 6.0 Powerstroke HFCM and now my rear filter housing on the ‘19 it’s nothing new to me, just the filter housing doing its job. More than likely it’s debris from the filling station either in their tanks or shavings from their pumps.
Yea i never pay much attention i was not concerned about the sparkles as it means the filter did its job lol
 

gimmie11s

Well-Known Member
Joined
Mar 30, 2021
Messages
2,345
Reaction score
3,475
Yay looks like i have 6 injector codes and a fuel pressure code when truck would not start this morning…… when i get back from work ill try it again but it would seem its time for the cp3.3 from what i can tell by the codes and last filter change there was some shiny sparkles ontop of the filter. Only 3 or 4 of them but they were there lol…..
Sorry to hear... how many miles?
 

Brutal_HO

The Mad Irishman
Staff member
Joined
Feb 1, 2020
Messages
12,033
Reaction score
21,370
Location
Douglas County, CO
As stated in the thread starter post,

PLEASE stick to the technical, TSB, and/or recall aspects of this issue.


Post your failures and any replies in the CP4 failure thread or start your own thread if it's other chit-chat.

 

Great White North Eh

Squish Cat - And So
Joined
Nov 10, 2019
Messages
1,719
Reaction score
2,831
Confirmed yesterday by diesel tech actually working on my 3500 that it is the new recall replacement fuel pump. Not the old / new interim replacement CP4. All parts are in and should be complete next week.
Hopefully the new computer program flash will help with Mpg as I was getting 10-12mpg prior to pump fail...
Take some pics of it when it gets out of the shop with the new pump please. See….see I stayed on topic ;), i think:p.
 

RVTRKN

Well-Known Member
Joined
Apr 4, 2020
Messages
421
Reaction score
276
There is no way it can “eat engines” really with the tiny injector holes anything that comes out would be hard pressed to do any damage but anyway after 30 mins of trying to start it i left it and called for a ride then just as my ride was showing up i tried one last time and it started no more codes so it was just a fluke it is -38°C out, it was plugged in but it has had no issue in colder temps so it is just strange had no issue on the drive to work…. I must say i an really impressed with how the batteries are in the truck its been almost 2 years with it running a plow and they still crank great even after 30mins of cranking in brutal cold weather….
Injector can stick open from the debris, over fueling a cylinder, or at least that is what I was told anyway. If it’s not true sorry!
 

Users who are viewing this thread

Top