Attention: TDR Forum Junkies 
Hey all,
I am down at the scales near Lex, KY and need to know if it is possible that the cp3 is bad. , or just the FCA.
The truck will run fine sometimes, but when it acts up it looses all rail pressure to the point of the truck dying. At idle, it will sit at 6000 psi on the rail gauge, and droop to below 3K or less then gun up to 10K-15K then idle fine. this goes on all the time now.
On the highway, it will cruise at say 70, and run about 15K on the rail gauge. When it acts up, it will not maintain speed and will act like you are pressing the throttle and letting off. it sometimes gets so bad that the motor is dead for 3-4 seconds then comes to life for 1 sec.
Things i've checked:
fuel filter - changed it and no difference.
Fuel pressure - no way to check lift pump, pressure, but it fills the fuel bowl with a couple cycles of the key with no engine start.
rail pressure releif valve - it did have a dribble at idle, so I blocked it off. Thought this was the fix, because it did run for nearly 90 miles before going back to leaving me stranded again.
I did remove the TST and EZ boxes. (I think the EZ popped the pressure releif valve because it was reading like 27K or more on the rail gauge. )
I was to be in Florida (gainesville) @ 11 AM. So much for that.
So, am I wasting my time with trying the FCA, and should I be changing the CP3 instead.
If the CP3 is the answer, can it be changed with hand tools on the side of the road.
Lastly, I do not have my CPL #, or engine serial #. Can someone tell me the Cummins part # for the CP3. (see sig, for truck info).
I am down at the scales near Lex, KY and need to know if it is possible that the cp3 is bad. , or just the FCA.
The truck will run fine sometimes, but when it acts up it looses all rail pressure to the point of the truck dying. At idle, it will sit at 6000 psi on the rail gauge, and droop to below 3K or less then gun up to 10K-15K then idle fine. this goes on all the time now.
On the highway, it will cruise at say 70, and run about 15K on the rail gauge. When it acts up, it will not maintain speed and will act like you are pressing the throttle and letting off. it sometimes gets so bad that the motor is dead for 3-4 seconds then comes to life for 1 sec.
Things i've checked:
fuel filter - changed it and no difference.
Fuel pressure - no way to check lift pump, pressure, but it fills the fuel bowl with a couple cycles of the key with no engine start.
rail pressure releif valve - it did have a dribble at idle, so I blocked it off. Thought this was the fix, because it did run for nearly 90 miles before going back to leaving me stranded again.
I did remove the TST and EZ boxes. (I think the EZ popped the pressure releif valve because it was reading like 27K or more on the rail gauge. )
I was to be in Florida (gainesville) @ 11 AM. So much for that.
So, am I wasting my time with trying the FCA, and should I be changing the CP3 instead.
If the CP3 is the answer, can it be changed with hand tools on the side of the road.
Lastly, I do not have my CPL #, or engine serial #. Can someone tell me the Cummins part # for the CP3. (see sig, for truck info).
