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Dual CP3 Issue

7K views 24 replies 9 participants last post by  01whitecummins 
#1 ·
So I have ats dual cp3's on my truck with new exergy %100 overs and new tubes. Less than 1000 miles on them. So I just got a weird surging issue going on at anything over 1/8th throttle my rail pressure will jump to 25k and the truck will surge 1/4 throttle and my guage gets pegged at 30k. Truck has lost a lot of power also. Was really smoky also before this started. Just got my UDC tune loaded up from firepunk. Any ideas on what I should check.
 
#2 ·
Forgot to mention I'm running a fuelab 200gph lift pump which keeps a constant 25psi to the cp3's. I still have the stock fuel filter housing in place. My rail is caped also. No hard starts and no issues at idle. Only code I had was #2 air intake heater relay. FCA TPS or bad stock cp3 or maybe my tune is what I'm thinking.
 
#3 ·
Im just going by what ive seen posted in the past. Are you using a d-max pump? If so, people are putting in a cummins fca. Also could be your controller, people are replacing it with the fish controller with great success.
 
#4 ·
To me it sounds like your controller went crazy and your pumps are pumping wide open. Before spending any money, I would recommend calling Firepunk and talking to Paul or Lavon since you just loaded a new tune from them before the problem started. They will probably want a datalog if you have those capabilities so they can see exactly what is happening to tell if it is tune or controller related. Another thing you may want to consider is an increased pressure rail pressure relief valve from exergy. The one I run is set to 240mpa (35,000psi) and is there to protect my engine and injectors because with bigger pumps and injectors, pressure spikes when letting out of the accelerator from a hard pull can reach 60,000 psi and could explode an injector. The new RPRV eleminates the possibility of this while still allowing a truck to run high rail pressure tunes as if it had the plug.
 
#6 ·
So if it is the fca I would think my issues would have started right off the bat, not 800 miles in?
 
#7 ·
Either the fca or the controller crapped out on you like you said if it ran fine for a while I'd lean towards the controller if so go with a fish controller


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#8 ·
Is there any way I could trouble shoot the controller? I'm going to try a new fca 1st I think.
 
#9 ·
There maybe but I don't know how to go about it I just know it's a common issue with the ats controllers I never even used mine left it right in the box. If you're going to replace the top fca get a cummins fca for it genos garage has decent prices on them


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#10 ·
Got a new fca on the way from Geno's. If that doesn't help ill try a fish controller I guess.
 
#11 ·
Took it for a short drive today no surging but at idle rail psi was 18k and under load it would drop to 10k. As I would accelerate it would drop down from 18 to 10. Would this indicate controller or fca. Got a fish controller on the way also.
 
#12 ·
Need to drop lift pump pressure. Sounds pretty similar to my symptoms with elevated lift. Try to get it under 18psi. I run 12-14psi normally.

Have you correlated that condition to being cold engine? For whatever reason, the ATS controller reacted more negatively when engine cold.
 
#13 ·
Ive ran 25psi since I finished my build. This is the 1st time I've experienced this issue. Ill try and drop it down once I get the new fca and controller on. As for temps I seen the issue happen more when its at running temp.
 
#14 ·
Try a fish controller. You should have 2 on hand anyway. Also datalog like they said.
 
#16 ·
EFI live or HP tuners. Not sure if udc or smarty pro can do it. Definitely get that lift pump pressure down, FCAs will not function properly at 25 psi. Should be 12 constant. Also get a pressure relief valve, way too easy for a rail pressure spike to trash the system with it plugged. T&C diesel can steer you straight with this stuff.
 
#18 ·
You have either a bad fca or controller. You can troubleshoot by putting the stock belt on. If rp is still crazy then there's your bad fca. If not, swap the fca from the top pump to the factory pump. If it runs fine again, you have a bad controller.
 
#19 ·
Got my fish controller today, gunna drop my lift pump pressure down to 12psi if I can. Also putting my pressure relief back in for now. Gunna call T&C to get one from them. I'm kinda worried that the 30k I seen damaged something.
 
#20 ·
If you changed the top fca to a cummins one you'll want about 17 psi if you left the dmax one in then yeah 12


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#22 ·
so if you already bought one I'd throw that in and set your lift pump at 17. i swapped my top pump fca before the kit was ever installed.
 
#23 ·
Well I cant lower my lift pump psi below 20, anyone have a fuelab pump and know how to adjust it. I think I might be putting in a regulator to control psi. I turned the truck on today to see how the rail psi acted with the new fish controller and it was still acting up, going from around 9k to 20k and then back down. I'm hoping this is because of the high LP pressure on the Dmax fca.
 
#24 ·
I have a 03 5.9 with the phatshaft 62 and on my edge tuner when I give it alot of throttle as soon as it hits boost the map sensor starts beeping at me anyone know what's going on there if it's bad or if I need a boost fooler or whatever it's called I have upgraded head studs 2 piece manifold head gasket bigger injectors the whole 9 just confused why it would be beeping at me
 
#25 ·
Well found my issue I think, after installing the cummins fca I still had the same issue. So I disconnected the return line on my lift pump and ran it to a bucket. Started the truck and everything was back to normal. I think the line might be kinked somewhere, gunna take the bed off and do some investigating.
 
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