P0251? Low power and hard starting

[DDouglas]

I have a 03 2500 4x4 auto,with a torq dog, nothing crazy, here lately it has seemed down on power and in the morning it will fire right up and run good ,but if you turn it off it will not restart, it takes about 10 minutes of setting and then it will fire up and run again. also if it idles for an extended time it will die. I have a p0251 code and have been told that has something to do with the FCA, but will it cause the problems that I am having? low power and hard starting?

 

[JApol]

from the 2005 manual

disconnect the connector on the CP3, should be a 2 wire connection.

connect test light between contacts, light should flash approx. 20 seconds after connection is made, check bulb intensity to direct connection to battery. if bulb flashes replace CP3



check for continuity between pin one of CP3 and pin 6 of connector C1 on ECM and pin 2 of the CP3 to pin 19 of same connector in ECM. if bad repair/replace wire.



With C1 of ECM connected check for less than one volt on pins 1 and 2 of CP3 connector, should be less than one volt. Make shure ignition is ON for this step.



With ignition OFF check for shorts to ground on both pins, should not be any.



Checks pins listed above on C1 for shorts to other pins in connector and shorts again to ground.



If everything checks good redo the light test in step one. If light fails to light repace ECM