05 4.7 cyl 2 misfire

[716Ram]

I appreciate you checking this out, I'm new on here and have never done the forum thing. I've got an 05 ram with a 4.7. Recently bought with 137k on it. It was driven on long highway trips as an old guys summer vehicle. We'll taken care of only had synthetic oil it's whole life. After having it for a month or so the money indicator light came on, cyl 2 misfire. You only feel it at idle and it's not a consistent miss every time it fires. I can watch it on the modis and it smoothes out after about 1500 rpms. So I did the usual, plugs were original, swapped them, no change. Swapped both the coil and injector with different cylendars and nothing fallowed. Installed noid lights on both the coil and injector to try and verify it's not a lack of signal from the pcm, they appeared fine. So I thought maybe a sticking valve. Performed a compression and a leak down test, found no problems . Threw a can of seafoam in the tank, ran some though the intake, and it really didn't smoke as much as I thought it would. I tried doing water decarbonization through the intake, and finally put some marvel mystery oil in the crank case as a last resort before pulling the valve covers. I'm curious if it could be a cam or crank sensor, ive seen them affect as few as 2 cylendars consistently but the fact that it smoothes out at higher rpms makes me lean twords something mechanical. I have probably put over 1000 miles on It since it started missing. Some 3 hr trips back home, and it hasn't really gotten better or worse. Seems to idle a bit smoother when it's warm or after a trip but still does it. Sorry for the long description but I like to give as much information as I can. Thanks for your help