what is the price to remove and replace the bank 1 cam shaft adjuster?

What is your question?

Car is a 2002 Audi A8. Engine was idling roughly and check engine light was intermittently blinking. Timing belt was recently replaced.

What makes this problem better or worse?

rough idling, but no problem when riding at higher speeds

How long has your 2002 Audi A8 Quattro had this problem?

one week