Help with codes p0011 and p0012
I'm new to the BMW world as this is my first. I have a 2004 330ci with 200k miles on it. I bought it three weeks ago. When I purchased it there was no SES and the car ran fine. After a couple days when cruising at a constant speed under 3k rpm the car would studder randomly. Felt as if I let off the throttle and quickly got back on it. Only happened when cruising, not when accelerating. I would see the rpm fluctuate. I also started to experience throttle lag, especially on cold starts. A few days later I did the oil change, used mobile 1 0w40 and a STP filter. That same day before the oil change I got a hard code for p0178 and pending for p0011.
I ordered the beisan system vanos seal kit to see if that would eliminate the codes. While waiting for the kit the studder happened more often and at idle, no matter what gear, the rpms would fluctuate causing the car to shake a little. Fuel consumption increased also and the fuel gauge wasn't reading accurately. Would read higher.
Upon replacing the vanos seals I didn't check the vanos piston, which is something I should have. After bolting everything back up I got hard codes for p0011 and p0012, p0178 is gone. The SES light comes and goes since then, and symptoms have remained the same but are most noticeable when the SES is on. I also think I hear a light tinker sound under the valve cover.
My question is could I still be dealing with issues from the p0178 code that are causing the other two codes? Possibly an injector issue? I was reading that the vanos piston and solenoid could be causing this along with several other issues. I can't find any concrete answers on solving this issue. I'd like to test things out first to ensure they are working properly before replacing things mindlessly. Any advice would be appreciated. Thank you