So my 2012 ram alarmed with a P0305 code and after some investigation I found that the rocker on cylinder 5 was not moving at all. with 218k on the truck, I found a used engine with less than half the kms and had a local shop swap for me. now with the new engine in, we have p0305 and p0308 showing up. we are at a little bit of a loss at this point since we have great (not sure the actual number) compression, spark and fuel. just to be sure the new spark plugs were rearranged as were the coils but the problem did not follow the changes. I am not sure where to go from here and my mechanic is in the same sinking life raft as I. any support that you can offer would be greatly appreciated as even my local dodge dealership is unsure what would cause this.

I should also mention that it is running rough as well so its not just a code that wont disappear. plan on going for a quick drive tomorrow to see if It just needed to stretch its legs or something but am not holding my breath.

 

What all was switched from the old engine? Have you pulled the plugs for cylinders 5 and 8 to see if they are wet with fuel or dry? Maybe the misfire is from fuel injectors not getting pulse or not allowing fuel through when pulsed. Were the injectors moved over from the other engine?

-Rod

 

Hey Rod,

Sorry for the delay but thank you for the response. I am not the guy doing the work at this point. I travel for work and just do not have the time to look at the truck and have brought it to a local shop. I am unsure if the plugs are wet or dry, but he did say that he was sure fuel and spark were good (didn't ask about his process of how to diagnose). when I last talked to them I said to pull the valve covers to make sure the valves were actually travelling as required. It would be weird that both cams have valve issues but possible.

I swapped complete engines with new plugs. we did swap injectors from the old engine from cylinders that were working with no change in the performance. New coils have not helped either.

 

Today the shop swapped injectors from cyl 5 and 8 to different locations on the fuel rail to see if the problem would follow. The codes were reset and did not come back. I have taken the truck for a rip an nothing seems to be a miss. looking like it may have just been a poorly installed injector or an issue with the electrical connection. either way I am happy to be driving the beast once again.

 

Great, thank you for the follow up post!

-Rod