Rough idle - yes I searched

[Bobtail_Bimmer]

As the title states I've read all that I could on the rough idle but still not 100% what im after. As you can guess my car has a rough idle but to an extent also continues as I drive. I can barely feel it as im driving. Almost like a slight shimmy or something. As I sit and idle its an in and out rough feel. Ny finace says she dosnt notice it but I do. The hotter it is outside the less it does it. This morning at around 70° it was slightly more noticable than this afternoon at around 90°. Just seems smoother as it gets hotter outside. Ive checked all hoses and replaced the plugs. Havnt gotten to the wires yet since im broke paying for my wedding. Ive pulled the PCV valve and cleaned it inside to where it was spotless. Still nothing has changed. Any ideas would be appreciated since I will be taken the 318 on my honeymoon and dont want to be stuck on the highway. Thanks in advance!!

EDIT: What im asking is that if you have had the exact same problem and replaced 1 certain sensor to solve it or made an adjustment please let me know. I hate to go and dish out a bunch of money and replace different things when all I needed was one item.

EDIT: Also, the previous owner was only runing 87 octane. I switched to mid grade and have only been useing Shell gasoline since all the others around here are garbage and stalls out other cars including my fiances. I put some seafoam in the gas in hopes of cleaning any injectors that might be clogged.