2002 Ford Ranger Edge 3.0L rough idle

I just bought the truck used with 66k original miles on it. While test driving the truck with the owner there was no rough idle or anything pointing to an issue of any kind. Well, a few days later I noticed that there is a slight rough idle while cold or warm. I did get a CEL while driving around town so I plugged in my code reader and got a P0122 for Throttle position sensor circuit low input voltage. I replaced the TPS and the CEL went off by itself, but the roughness in the idle is still there. I have not been able to find a vacuum leak(might not have looked in the right place?) I have cleaned the MAF, replaced plugs and wires with OEM, changed air filter and fuel filter and cleaned the IAC and replaced the cam position sensor and synchronizer and so far the idle hasn’t changed. No better no worse. The coil pack is my next item to look into.

The “Rough” idle feels like a misfire. I am getting no codes or CEL in regards to the rough idle at all. I don’t know what else to look for and like I said above….I may be over looking a vacuum line somewhere I just don’t know.