I had the factory recall of the torque converter fixed. Then my van started misfiring, BAD!!!! So, I take it in and they say I need new spark plugs, catalytic converter, muffler. And then call me back and say van is still messing up. They replace the ignition coil too. My FIL says that the torque convertr replaced might have been the cause of this problem if it was faulty. Is that true?