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CP3 acting WEIRD. Very detailed symptoms.

16K views 14 replies 5 participants last post by  Dustin t 
#1 ·
Ok so I've been trouble shooting for a good while now almost 2 weeks. I've narrowed down and eliminated a lot of possible problems. My CP3 rattles in a pattern not constant. So the first time I started my truck after codes and noise came up it was still at operating temp and it literally starts no problem in two cranks or whatever just like half a sec I turn the key. I have no blow by what so ever. I park it and kill it. Waited till it was cold (80F) outside. Then I start it and still fires up no problem but the rattle is still there and sounds like an old 7.3 ps. It's loud and idles stupid. 750 to 600 then to 750 then to 800rpms. I tap like not even 5% throttle and it climbs to 1200 and stays there and sometimes it won't stop climbing but won't go passed 1600rpms. And takes for ever to go back to 750. Blows a lot of black smoke for being stock. I will add I had a smarty S06 on level 7, that 160hp with added timing and BD boost fooled but took smarty off about 2 weeks ago to let a buddy put it on his 05. Before it really acted up I was coming home going 75mph on a interstate and I just had filled up to full. I had the cruise set and I could watch my exhaust just blow black smoke the whole time. A 30mile drive and I lost almost a whole quarter of fuel and I get 19mpg high. Throws codes P0088 P0148 and P0251. If I remember right ones about regulater, then fuel pressure has exceeded max, and fuel delivery error. My psi at idle is 26,000! Fuel bowl is still holding the right amount so I don't think my in tank pump is have a hard time supply to cp3. I also found out only one stud and nut was holding it in. I literally didn't run for 5 days because I got busy. The day I started it just to see if it acted different for not starting it for so long. And it did. It started quick and idled perfect. Right as it fired the motor shook for a sec and just a haze of white smoke not even for a sec. I killed it and deleted codes and started again. Codes did not come back. I decide to drive up our long driveway and once I hit 25 it did the same thing and bogs up and down and up and down. But still no code?! Parked in same spot and killed it. I left it sitting until the block was cold. Started it and sounded like crap again and then only one code showed up, "Fuel Delivery Error" that's it. Can having one stud and nut holding it in tight still cause this? Why is it pushing 26,000 psi instead of 6800? Why start fine after 5 days when very important codes pop up? No leaks around cp3. Checking to see if steel lines where out of alignment and they weren't. Should I just replace it since it's got 156,000 miles on it? I'm in the position to replace both cp3 and injectors. I got frustrated and fired it up and power braked it to 2000rpms and only let of throttle, the rpms drop really fast and the turbo goes "WOOP WOOP WOOP WOOP" real slow and loud and the motor fires dumb and a loud pop comes out the back to finish it. When I let off the throttle it's supposed to go back down slow. I'm probably going to replace idk. Please and thank you!
 
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#3 ·
Throws codes P0088 P0148 and P0251. If I remember right ones about regulater, then fuel pressure has exceeded max, and fuel delivery error. My psi at idle is 26,000!
For some reason ECM failed to regulate the cp3 output through FCA.
The FCA acted like it's unplugged, fully opened.
So it's either the FCA, the ECM or the wiring connections between the ECM and FCA.:smile2:
 
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#4 ·
If the motor runs normal at idle (not loud and normal rp) and there is no P0251 but P0148 shows up on highway then you have issue with the injectors (most of the time) or CP3 or the lift pump.
 
#5 ·
Having a similar problem on a customers 06, P0088, P2509, P0251 pressure maxed out at 26k. Have verified integrity of wiring and connector between FCA and engine computer and having substituted a known good pressure switch it needs an ECM.

We are just now getting into programming modules having purchased the Matco Jbox. Does anyone have any advice for a first timer, thanks.
 
#10 ·
ECM control FCA with PWM signal.
When PWM signal is low or FCA disconnected, FCA is fully opened.
When PWM signal is increased FCA move to the closed position to limit fuel flow to CP3.
If pressure maxed out at idle then FCA stucked fully opened or there was no PWM signal to FCA.:wink2:
 
#12 ·
Update! New Cp3 is on! Sooo much restored power! Still one sore problem. My truck is throwing the code P0251 "Pump Regulator Control". Now for the first 30 min no noise and no codes, basically runs very good. Still blow black smoke but it's been cut in half. So I'm definitely in need of new injectors. When the code showed the same knock came back but this time I had perfect throttle and the motor would not bog down or studder. Loud knock no power loss. No white smoke at all. Could it be crankshaft sensor? My wiring is all good. I do think my bad injectors can cause this. Ones stuck open or spraying to much. Just one more random question. Can my valves be set too bad to cause this?
 
#14 ·
My truck's symptoms were loud knock and white smoke. One of my injectors was stuck open, thus spraying fuel into the cylinder 100% of the time. I replaced that one injector, that was 5 years ago. It's still running great.
 
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