Has anyone had a CP3 quit on them? What are the symptoms?

I have had a study decrease in power and increase in smoke and egts over the past few months. I have changed injectors, fuel filters, lift pumps, adjusted valves, checked for boost leaks, and checked turbo. I could never find anything.

I was getting a P0251 code every couple of days so I changed the FCA. That fixed nothing, so I went back to Smarty Revo and pulled the Quad race. P0251 code went away and never returned. Truck ran a little better for a few weeks until last Friday. I could barely make it up hill without fogging out traffic and hitting 1500 degrees. I could not maintain speed. Fuel pressure started to fluctuate and then leveled off. Not sure why. I can't tell you what rail pressure was because my gauge has been back ordered. I barely made it home that day. Truck stalled out. F.P was at 30 psi. Got home, finally, and removed rail pressure line to find barely a drop of fuel! Return line was about the same. Sooooooo. Sound like a CP3 gone bad?

Sorry for the length!

Bryan

 

you might want to try a rail cap FIRST before sinking money into the cp3. rail cap is around $50. it may be the cp3, but they are pretty reliable.

 

I forgot to mention, during my troubleshooting process, I capped the rail. That was done the same time or shortly after I went back to Revo. Even though the rail relief valve had been leaking, I notice no difference in performance after the cap.Thanks

Bryan

 

Did you check the COV (Cascade Overflow Valve) on the CP3? Could be dumping.

MikeyB

 

I did not check the COV. It would not completely dump all of the fuel. It would at least run. It won't run at all, but 10 seconds or so. As I understand it, the valve bypasses fuel to cool the pump at 3 different intervals. Even if it stuck open, I could at the very least have an underpowered running truck. We'll see what happens when I change the pump. I just can't see it being anything else but there is always the possibility.

Bryan

 

Well, it wasn't the CP3. I swapped a known good CP3 and FCA in and I get the same thing.

Issues:
1.) Smoke at idle
2.) Poor throttle response
3.) High EGTs
4.) Tons of black smoke when driving
5.) Once coolant temp rises, truck is not drivable and stalls out

Checked:
1.) Fuel filters
2.) Swapped CP3 and FCA as a unit
3.) Changed walbro lift pump
4.) Checked boost boots
5.) No fuel in oil
6.) No oil in coolant
7.) No fuel leaks
8.) Checked injector tubes and lines

The only thing left that I can think off, would be head gasket and injectors or a dropped valve seat. The only problem is I don't believe I have the symptoms of either.

The injectors are a few months old. I would hope nothing is wrong in that department. Anyone have some ideas? I'M IN DESPERATE NEED OF SOME HELP

Bryan

 

Are you still getting the 251 code? Check the rail pressure sensor. I guess the pump didn't do it for you.

 

I can't get the truck to run long enough for any codes. But no, no codes! maybe I have an injector or two stuck open and it is over fueling. Just didn't seem like the logical route to go. I'll have to disconnect one at a time tomorrow and see if I can't find one bad. I guess I may be needing injectors, again!

Shane I appreciate the help bud! Way to step up for me. Let me know when that other pump is available and I'll get these two out.

Bryan

 

Maybe intake air temp sensor?

I don't know if these can go bad "enough" to give the symptoms your having though, without setting a code.

When did the plastic intercooler end caps go away? Might check them if they were even still used in '05.

jeff

 

The only thing I see with this is, if the injectors were stuck open you would be overfilling your crankcase and you would be able to tell. It truely sounds as if your engine isn't getting air. What kind of boost numbers are you seeing?

 

For what is worth I agree, you did not mention checking/changing the air filter. Try running it at idle with the air filter off.

 

Did you ever get your truck running again? I've got a guy with similar problems.

 

Yeah I did. Believe it or not it was the Boost sensor(MAP) located just to the left of the fuel rail. Couldn't believe that a $70 part could cause that many issues. I would have swore it was something more severe.
Running strong as ever!!