Great work by 1st Class on a very difficult situation with my BMW. Started with a need for de-carbonizing intake manifold based on sluggish performance upon acceleration, then moved to cracked #5 spark plug and bad coil, then on to X-Drive transfer case replacement. Had third-party extended warranty policy from a company that didn't want to pay anything. 1st Class communicated with the warranty company and convinced them to pay some of the bill.
