No problem. If you fix the leak and the Sensor and the plugs, you should test for the misfire. If it's misfiring a simple trick is to take a money bill (any denom) and hold one end up to the tailpipe. If it flaps around wildly, no misfire. If it SUCKS IN the bill like a lot and towards the pipe, then you have a misfire. Test it after the repairs and find out. If it's completely done misfiring, it probably solved your problem and you should have it retested. Even if you fail it gives you valuable insight. If the numbers changed at all and I mean by like more than 5 ppm, you know you're getting on the right track and something you did affected it.