I had to replace temp sensor in my 2002 zetec dohc engine. I finished drove car and noticed a battery light. I realized I forgot to plug in alternator so I plugged it in cranked up and everything was fine for a second then suddenly I got a cylinder 2 and 3 misfire. I opened hood and noticed my alternator wires were hooked around the altenator positive wire terminal in such a way they were shorting out. So I have a cylinder 2 and 3 misfire as if I shorted something with my altenator. Maybe the coil pack? I unplugged cylinder 2 and 3 and car runs worse.