08 X5 with idle surge and vibration issues

[EMT760RR]

Hello everybody,

I'm having some strange idle or vibration issues on my 2008 X5 with a 3.0 N52. Back in October on a road trip up to Oregon, it had gotten significantly worse on cold starts and coming to an idle at a stop light. I decided to take it to a independent shop in the area. They claim to have pressure tested the intake system but no leaks found " supposedly". They found that my valve cover was leaking oil into one of the spark plugs. Convinced they decided to charge me for a valve cover job. Quite expensive. It did improve the vibration a little bit. Previously I changed all the spark plugs with NGK iridiums. The OEM plug I believe.

Frustrated after the problem came back. I decided to take matters into my own hands recently and I cleaned my Vanos solenoids, the bottom one was covered in oil. Doing that just seem to improve my acceleration and torque issues. However the vibration and surging is still present. I'm convinced either my disa valve or something else is leaking as I can hear hiss. I checked the boots on the intake system I don't see any noticeable tears or cracks.

I will say that my AC belt needs to be changed eventually as it's glazed maybe a pulley is seized and it's causing a low idle problem? I have inpa software and I scan for codes I don't see any noticeable ones that would indicate a bad coil pack or anything like?