Originally Posted by DL
If it was me, I would start now. With the CPO warranty, you have to deal with the $50 deductible. It took six months, and multiple trips to the dealer going through the BMW "process" starting with the lifters until BMWUSA approved the new cylinder head. Depending on the time duration in your own individual case, I would rather deal with it this time of year and enjoy the Z4 during the warm weather IMHO.
Thanks for the advice! As soon as the weather improves and the car roads are dry, I'll drive this up to the dealer.