been fighting this code like many others for several months. had new 60 hp injectors installed a month ago- injectors have been pulled since then and tested- they are good. still had code after injector install. called todd at t&c diesel. he had me unplug my fca while truck is running and determined my prv was bad. got one of his 30k prv's and cleared the code and truck was fine for two weeks until yesterday. on the way home from work truck lost power, would not go over 20mph and i had heavy smoke. shut the truck down and restarted and the truck ran fine as it did this morning! the only difference this morning i noticed (the truck running fine) my boost levels are low! cruising at 55mph my boost is only 0-1 and at 60mph my boost is only at 2-3- but if i put my foot down i can get the boost up to 40 easily. i also had a buddy a couple of weeks back hook my truck up to his snap on scanner and my rail pressure seemed good- around 7000 psi at idle. i may only experience this problem once every two weeks. any ideas? can the cp3 be ruled out since when i shut the truck down and restart her she runs fine??

 

Do you know what the pressure is at the CP3 from the lift pump? Is that good when the truck starts acting up?

It could be simple as the FCA sticking.

Also have you check the wires from the alternator? There was some discuss in the past with the '03 early '04 where the alternator wiring would short out on the block & cause the engine to run rough.

Keep us posted on what you find.

 

tesla440 i do not know the pressure at the cp3. can that be done with a scanner? i will check the wires at the alternator- i did not know this was a problem. thanks.

 

somebody mentioned to me today to check the overflow valve on the back of the head. says the spring could be weak or broken if it saw more that 14psi. did a google search on this-catch find any info relating to 3rd gen trucks.