Help diagnose VANOS solenoids!

[Macky65]

Hi all,
If there is a thread dealing with this specific issue, please direct me to it. I've searched everywhere.
I just bought an 2010 X5 30si w/80,000mi. It started throwing P0012 codes (just a home scanner)and rough idle. After cleaning and no success, i replaced both VANOS solenoids with new Dorman solenoids. Now it shakes violently at idle, both cold and warmed up.
I unplugged both VANOS solenoids, and it fixes the shaking. To isolate the bad solenoid, I plugged in only the exhaust solenoid, no shaking. Plugged in just the intake solenoid, no shaking. Plug then both in, violent shaking.
I'm perplexed as to how this could be. Does unplugging one solenoid turn off the whole VANOS system? Any help in the right direction would be greatly appreciated.