The oil seal in the turbo could be wiped out causing your smoking issue.
As for the fault code your rear main crank seal could be leaking.... and when i say leaking i mean sucking in air and causing a running lean issue. At my shop we have replace a lot of rear main seals just this year on the 2.0T engines.
What is your learned fuel adaptions in the ECU
what is the Air leak adaptations in the ECU.??
Lee