About a month ago my truck started running very rough at idle and was knocking real bad. I took it in to the dealer and they said it was a fouled injector and a bad injector connector. The fixed it under warranty and the problem went away.

Now, the truck is missing again, but it doesn't do it all the time...and it isn't knocking. Is there something besides a fouled or bad injector that could cause it to miss? I can tell that it's missing on at least one cylinder...and sometimes it feels like it might be missing on two of them.

I poured three cans of Sea Foam into a full tank of diesel to see if that would help. I think it may have helped some but still, every once in a while, it will start missing again.

Any ideas on what could be causing this and why it only does it some of the time?

 

Do a search on the FCA valve on the CP3. Seems that this could cause the issue. From what I remember when it starts missing at idle, unplug the connector going to FCA. If the idle makes no change then your valve is sticking. You can replace with a new valve. I hear they sell them now so you will not have to replace the whole CP3. Hope this helps.

 

Uhhhh...10-4...I guess.

 

hoss the fca is a valve that controls fuel from the cp3.

 

Fuel Control Actuator or FCA...