Ignition issues can be a real pain to both diagnose and deal with. Sure, generally speaking, having a faulty ignition coil is a better problem to have than a worn-out turbo or clogged DPF, but ...

You're hunched over the engine with your wrist painfully contorted, wishing you were Mr. Fantastic. You've finally removed broken spark plug number four and then the intrusive thought hits. "Should I ...