Rough running 04 CR

cranked_dodge

cranked_dodge

Diesel Pro
Joined
Jul 31, 2007
Messages
1,103
We have a customers truck here that is acting up.

The truck is a 04 Automatic with the following mods:

Built motor by us
Scheid Street Cam
Dual CP3 Pumps Stock Bottom 35% up top
45 LPM injectors
S474 add a turbo kit over a Silver 66
Smarty TNT-R

Now the truck had injector issues to start with and we replaced the 100hp injectors in it for a set of the 45 LPM injectors. Truck ran great he went to a few drag races and never had an issue we played with his tuning and got him getting faster and faster.

Now in the fall he called up and said his truck was acting strange, if he took it easy he could drive no problem but when he got his foot into it it would spit and sputter and knock and run real rough.

There are no codes coming up.

I have changed the dual CP3 controller changed the tuning from stock to a few in between.

Now I am at a loss as to what it could be. It will also run rough not under a load when I rev it up to about 2500 rpm it will idle there for a little bit then rev up and then fall off i checked the rail pressure and it is going all over the place.

I just need a place to look next.

Thanks
 
Check the rail pressure relief valve and the FCA's on the pumps. Either you are losing rail pressure thru the valve or the cp3s are not supplying the fuel correctly.
 
Or your lift pump is having issues. Is your lift pump supplying constant pressure, or is it dropping off?
 
Injector tubes are all tight and good. Rail pressure relief is blocked off so cant be that.

Is there anyway to test the FCA on the pumps?

I will check his lift pump. it is a 150 Fass but who know when he changed his filters last
 
cranked_dodge said:
Injector tubes are all tight and good. Rail pressure relief is blocked off so cant be that.

Is there anyway to test the FCA on the pumps?

I will check his lift pump. it is a 150 Fass but who know when he changed his filters last
Click to expand...

Disconnect the electrical to the fca, it should go full rail pressure, makes a horrible racket at idle. I would probably just to swap each one, one at a time for a known good one to isolate which one was the issue. 3 torx bolts and about 5 min of work.
 
Last edited:
Could be injectors again. Just had a set with the stators pushed up in the solenoids. Can cause some wierd problems. duals and rail capped is a good way to get the stators
 
rail psi sensor can cause strange things like that to happen. It's worth a try to replace it.
 
You must log in or register to reply here.
Top