LML CP4 Problems
- Thread starter Janimal444
- Start date
There has been some real shitheads show up around here lately, it's almost daily some clown breaks his shit and blames someone else or some tree huggr shows up telling us we are all going to hell :roflmao:
Yea, but if they get out of line the community seems to run them off pretty quickly...
Why not?
Why build a duramax? Why build a rail? Why build anything? Because we can and feel like it.
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Also just so everyone is aware there no magic update onncp4 pumps that happened in 13 or 14 they fail on brand new trucks just the same as the 11-14s.
My lml has a fass and gets additive and bone stock otherwise once I have the money for a cp3 swap and egr delete away everything goes.if I can hold out that long anyway 2600 miles has been rough not having some fun with it :roflmao:
My lml has a fass and gets additive and bone stock otherwise once I have the money for a cp3 swap and egr delete away everything goes.
if I can hold out that long anyway 2600 miles has been rough not having some fun with it :roflmao:
I must be lucky...
287k on my cp4
2011 LML 3500
Sent from my Nexus 6P using Tapatalk
287k on my cp4
2011 LML 3500
Sent from my Nexus 6P using Tapatalk
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I know why. lol
I just don't see it when its your driver truck. I like power as much as anyone but some things you just leave alone. I bought a new truck in 2006 with full plans on racing and pulling it. That truck never seen the dealership again. I would never do what I done without plans on fixing or paying to fix anything I broke on it. I have young guys in my shop wanting to do deletes and I tell them they would be a fool to touch the truck!!! I run off more work than I get but I have a conscience and just cant do that to someone knowing what could happen and what it would cost them. Just my opinion which is worth nothing.:hug:
I just don't see it when its your driver truck. I like power as much as anyone but some things you just leave alone. I bought a new truck in 2006 with full plans on racing and pulling it. That truck never seen the dealership again. I would never do what I done without plans on fixing or paying to fix anything I broke on it. I have young guys in my shop wanting to do deletes and I tell them they would be a fool to touch the truck!!! I run off more work than I get but I have a conscience and just cant do that to someone knowing what could happen and what it would cost them. Just my opinion which is worth nothing.:hug:
I am curious, exactly who on this forum told you to tune your truck? You have exactly (10) posts on this forum, all in this thread. I do not see any posts where you asked advice on tuning your tuck, before you did it? Most new comers on here are advised to leave their trucks STOCK, because once you start to mod them, it's an expensive / slippery slope.
If you are able to drop $65k on a new truck, one would believe you to be a full grown adult?
Being a full grown adult, how about you try taking responsibility for your own actions.
Someone plugged a tuner into the OBD port on YOUR truck, I'm willing to bet that someone was YOU! Own your own decisions.
It's guys like you that sue McDonalds for making them fat, rather than admit it's them, that keeps shovelling Big Macs down their throat!
I am lucky, too. 511k on my CP4, 2011 LML 2500HD and I run Power Kleen grey bottle at every fill up.
mine shit the bed last week. 47k miles. clogged 5/8 injectors, last 3 were returning large amounts of fuel.
running hot tune not max effort, full delete, etc. truck very well taken care of too, definitely what frustrates me, along with obviously the pricetag of the truck and the repair
shop who does my work has a 2016 with 8k miles having the same thing done.
sdp cp3 conversion going on with an airdog 165 II-4g and of course, new injectors.
running hot tune not max effort, full delete, etc. truck very well taken care of too, definitely what frustrates me, along with obviously the pricetag of the truck and the repair
shop who does my work has a 2016 with 8k miles having the same thing done.
sdp cp3 conversion going on with an airdog 165 II-4g and of course, new injectors.
I would do a new injector return line assembly with check valve, and replacing the rail pressure sensor and electric relief valve is also a good idea. They might get by OK for a little while, but you dont want to end up stranded somewhere because of one of these items failing not long after the repairs.
he removed the whole fuel system to send out and cleaned at the same place that benched my injectors. If any of it is bad, he already knows to replace it. It's just money right
So I have a 2015.5 and so does my step dad. Both are 3500 duallys I have 226k miles and he has 254k no problems. His buddy has a 13 or 14 2500 with well over 300k with no probs but my brother has a 15.5 2500 with 140 and his just took out the whole motor from what I heard yesterday....... all the trucks are used to transport campers all over the country. Mine and step dads have been tuned for the past 40-70k miles just for fuel economy and emissions. Was told it was a 40-50hp tune
just so there is no confusion. bosch made no meaningful "updates" to these pumps since their introduction to correct the problem.
the biggest updates was coating changes to the roller follower and new body alloy (high silicone cast aluminum). the issue of the roller getting jammed up and not rolling on the cam will not be solved by this. also the bigger issue that seems to occur is the roller (and follower) turns 90 degrees to the cam and has no way to roll. this grinds a groove in the roller and cam sending metal into the fuel system.
all CP4s suffer from these failure modes, whether it is a CP4.1 or CP4.2. the design of the pump is the problem here. added lubrication MAY help extend the life of the pump but it seems that pumps still fail regardless.
the TDI club has this well documented with the CP4.1 used on the VW TDI
http://forums.tdiclub.com/showthread.php?t=299854
and
http://forums.tdiclub.com/showthread.php?t=286380
and of course my thread
http://forums.tdiclub.com/showthread.php?t=387252
the best guess and evidence as to why Bosch would make this change is to lower the cost of manufacturing. the CP3 has an almost all high strength steel body to handle the pressures, plus three precision ground/machined pistons, valves and related parts. in the CP3 each piston only makes one pressure stroke per a revaluation. the CP4 piston makes two. this is twice the strokes
the CP4 only has a steel piston head that retains the pressure. the body is all aluminum. there is only one piston in the CP4.1 and two pistons in the CP4.2. the parts count on the CP3 is several times higher than a CP4. being that a CP4 retails for roughly the same cost as a CP3 this was likely a way for bosch to increase profits. bean counters likely designed this pump.
what doesn't make sense is now they are paying more on the HPFP warranties along with replacement of contaminated parts as a result. whether they come out ahead is anyone's guess
luckily i am still driving an LMM so i don't have to worry there but i did experience a CP4.1 failure on my VW TDI. right now i am in the process of collecting the parts needed to convert that over to a CP3/R70 pump.
If my duramax had a CP4, converting it to a CP3 would be one of the first upgrades i did after the warranty was up
the biggest updates was coating changes to the roller follower and new body alloy (high silicone cast aluminum). the issue of the roller getting jammed up and not rolling on the cam will not be solved by this. also the bigger issue that seems to occur is the roller (and follower) turns 90 degrees to the cam and has no way to roll. this grinds a groove in the roller and cam sending metal into the fuel system.
all CP4s suffer from these failure modes, whether it is a CP4.1 or CP4.2. the design of the pump is the problem here. added lubrication MAY help extend the life of the pump but it seems that pumps still fail regardless.
the TDI club has this well documented with the CP4.1 used on the VW TDI
http://forums.tdiclub.com/showthread.php?t=299854
and
http://forums.tdiclub.com/showthread.php?t=286380
and of course my thread
http://forums.tdiclub.com/showthread.php?t=387252
the best guess and evidence as to why Bosch would make this change is to lower the cost of manufacturing. the CP3 has an almost all high strength steel body to handle the pressures, plus three precision ground/machined pistons, valves and related parts. in the CP3 each piston only makes one pressure stroke per a revaluation. the CP4 piston makes two. this is twice the strokes
the CP4 only has a steel piston head that retains the pressure. the body is all aluminum. there is only one piston in the CP4.1 and two pistons in the CP4.2. the parts count on the CP3 is several times higher than a CP4. being that a CP4 retails for roughly the same cost as a CP3 this was likely a way for bosch to increase profits. bean counters likely designed this pump.
what doesn't make sense is now they are paying more on the HPFP warranties along with replacement of contaminated parts as a result. whether they come out ahead is anyone's guess
luckily i am still driving an LMM so i don't have to worry there but i did experience a CP4.1 failure on my VW TDI. right now i am in the process of collecting the parts needed to convert that over to a CP3/R70 pump.
If my duramax had a CP4, converting it to a CP3 would be one of the first upgrades i did after the warranty was up
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One thing Ive always wondered about the CP3 swap is how does a CP3 maintain the higher PSI that the LML requires (not to mention the fuel volume) when its essentially "half" a CP4?? Just curious.
An excerpt from truck trend
"The CP3 is a radial-piston pump that can supply up to 29,000 psi in some applications and is perhaps the most well known and most modified high-pressure pump on the market."
"Next is the CP4, which is also made by Bosch. Although it has a higher number designation, the CP4 actually flows about 20 percent less fuel than its younger brother, the CP3. Found on ’11-to-present Power Stroke and Duramax engines, the CP4 is a more advanced pump despite flowing less fuel, with external high-pressure circuits and a maximum pressure of 29,000 psi."
"The CP3 is a radial-piston pump that can supply up to 29,000 psi in some applications and is perhaps the most well known and most modified high-pressure pump on the market."
"Next is the CP4, which is also made by Bosch. Although it has a higher number designation, the CP4 actually flows about 20 percent less fuel than its younger brother, the CP3. Found on ’11-to-present Power Stroke and Duramax engines, the CP4 is a more advanced pump despite flowing less fuel, with external high-pressure circuits and a maximum pressure of 29,000 psi."