I have a 2003 Dodge Ram 4.7 which recently had the spark plugs changed out. Ever since then it has been idling rough and has stalled out a couple of times. A fuel smell is more present now and the PO44O code is popping up. I have visually checked all the hoses for cracks and have found none. I took the tube off the PCV and it still has good suction to it. Appreciate any assistance

Thanks for the reply, in response to your possibilities of what the problem might be. The PO44O code has been present here and there for years. Early on Dodge (service dept.) said it was the O2 sensors so after going back and forth a couple of times with the same issues a mechanic told me about the gas cap scenario. That work for about six months and then the code comes back and has been like that since. How do you test to see if its the solenoid and to determine if the canister is plugged orif its not working properly? Thanks for the reply, in response to your possibilities of what the problem might be. The PO44O code has been present here and there for years. Early on Dodge (service dept.) said it was the O2 sensors so after going back and forth a couple of times with the same issues a mechanic told me about the gas cap scenario. That work for about six months and then the code comes back and has been like that since. How do you test to see if its the solenoid and to determine if the canister is plugged orif its not working properly?

When I took the plugs out the gaps were consistently .065 and not in too bad of shape. I set the new plugs at .040 as per the manual (Haynes). It wasn't running that bad prior to me changing the plugs but I figured I had well exceeded the recommended replacement for the plugs as per the manual. I also had prior to the change of the plugs and PCV codes PO456, PO441 and the ever present PO44O. But with all that it still was running pretty descent but as you could assess the gas mileage wasn't good. When I took the plugs out the gaps were consistently .065 and not in too bad of shape. I set the new plugs at .040 as per the manual (Haynes). It wasn't running that bad prior to me changing the plugs but I figured I had well exceeded the recommended replacement for the plugs as per the manual. I also had prior to the change of the plugs and PCV codes PO456, PO441 and the ever present PO44O. But with all that it still was running pretty descent but as you could assess the gas mileage wasn't good.