Installed the stage 2 pump on Saturday.Ran great.Monday had a touch of rough idle but cleared up after few seconds.Took a run around the block today and the rail pressure would drop when excellerating, but recover under light throttle.Came home checked everything over.Found nothing obvious.Went to go for another drive and got about 200 yards down the road and it started trying to stall out.Limped it back and it completely died in the driveway.It will crank back up and hold 7k psi RP but it steadily falls to 3k psi and then dies(takes about 15 sec.).Pressure falls real smooth,nothing erratic.Will do this every time its cranked now.Unhooked the FCA and cranked with the same results.Got the pump NIB from Nathan(MPI).Said he will call John tomorrow.

Any ideas on whats causing this?I'm dead in the water, sent the core back yesterday.
Thanks

 

Do you have a rail block off?

 

I would say,... especially when you acknowledged that it ran great at first that a tiny bit of thread broke off from the install and went into the cp3. I would bet a simple disassembly of it and the FCA will uncover the problem. It's not the pump or it would have screwed up at the git go, IMO.

 

Im sure John can diagnose it. A phone call will probly fix it. What size fluxes you runnin?

 

No rail block off. This problem just kinda popped up out of the blue.Running great, now won't run.Never got on it real hard since installed.Should I check the FCA or will this void warranty(lots of red tamper stuff on all the bolts).

 

Running flux1's for now.Hope to have some flux2's in before long

 

Let me first get this out-----
To all who may try and install their own cp3; If for any reason you think any debris has gotten into the pump, do not start the truck. The tolerances are wayyyyy too tight for things to pass threw. Things can and will get threw the FCA that will hurt or kill a pump. I hope this is not the case with Homewreckers' pump, but let it be a lesson learned possibly the hard way.

OK, Homewrecker,
It sounds like you have ''hung'' one if not two plungers/pistons in the cp3. The pump will have too be sent back. If a plunger is hung, the pump is trash and will be sent to be melted down. Do not tamper with anything. You were smart to see the red tamper proof element we put on them and not proceed further.
I hope the FCA is the only problem we find, but unfortunitly, it does not sound good at this point. Please PM me your phone number and a good time to get ahold of you so we can talk tommorow.

Thanks,
JD

 

I was regreting letting that diesel shop install my pump cause I wanted to do it myself until right....about..........NOW.

 

This really sucks!

 

Sorry man, I hate given bad news. Don't get worked up until we diagnose the problem. Get that PM sent so we can get you back on the road before the Revolution hits.

 

I hate to hear it man. I hope its just an fca problem. Did you try runnin it with the fca unplugged?

 

Is it possible it could be a bad prv? Im just guessing here. Maybe thats why jd was askin about the rail cap, DUH.

 

Tried it with the FCA unplugged.Same problem only RP was at around 10k at idle,but it still slowly ramped down and died..

 

I'm bummed at the thought of pulling this thing again but life goes on! Jd and John have both messaged me and said this will be taken care of first thing in the morning.John even said if need be he would get another pump on the way.Now I know why Floor-It is so highly recommended.Thanks JD and John.Will be waiting on that phone call in the morning

 

This sounds to me like the low pressure/supply side fuel is weak.

As you describe it:

It will start and run for a little while and then slowly the rail pressure will drop.

Seems like the CP3 is starving for low pressure/supply side fuel.

Whats the fuel pressure from the lift pump system? Filters clean? Any chance you have a microbe/algae problem that plugged the filters?