Got the car back last Friday. The fuel injector in cylinder 2 was fouled, so they replaced that, and I had 3 bad ignition coils. Coil-on-spark ignition is a good thing for efficiency, but it doesn't do much for reliability when the coils are wired in series. Once one coil goes, all of the coils that follow it on the circuit will fail soon after. Limping the car to the shop probably didn't help things.
By now, I've lost all faith in the Volkswagen Group to produce a car with a reliable electrical system. I've had 5 bulbs fail in the taillights, a faulty fuel pump that reported as an electrical failure, these ignition coils, and one incident when changing radio stations caused the sunroof to spontaneously open. If you have a joke about '70s British cars, feel free to substitute VW at any time.
If Infiniti built a G35x wagon, I'd have one by now.