Hello all, little info on car
2008 r56
1/08 build
N12 engine / auto trans
98k on car

My wife told me car was running rough but i didn't think it was that bad until i took in for tires on Saturday.

cold start, rough idle and very poor throttle response. Pull codes and there are a few. Main concern is "vanos intake" 287D
quick search didn't find much and wasn't one of the easily addressed vanos failures it seems

also stored is transmission K-can bus off CF2D
trans down shifts poorly and sometimes hesitates going down a great. Up shifting is ok other than car falling on its face after shifting up a gear.

just installed new oxygen sensors, thermostat and water pipe. Valves looked super clean when i had intake manifold off the other day. I know this isn't related to vanos but just giving all info possible


thank you for any and all help

 

Pull both VANOS solenoids and check them for debris and buildup, it only takes a couple of specs of debris to make them malfunction. While they're out give them a dousing of brake clean and reinstall & clear the codes. If the fault returns chances are the intake solenoid is either electrically faulty or stuck.

Start there and then work towards the transmission, these cars make the autos do weird stuff when the engine isn't happy.