P0011/0021 codes--Not good signs.

The timing is most likely off on both banks. I would not run the engine any more until you get it retimed in order to prevent catastrophic failure to the engine. Probably best to replace the chain guides and chain, too. This is labor intensive, $3-6K or more depending on labor cost and the work needed. Best to get BMW INDY to look it over.

Did you rule out the VANOS solenoids and/or the camshaft sensors?

__________________
2003 X5 4.4i Titanium Silver