So today my truck started to misfire again. Bout two weeks ago I had a number 7 misfire so I replaced the COP and that fixed it now I have a number 2 misfire and I'm goin to replace the COP on that one as well. I was wondering if there is something more goin on that would cause all these COP to start goin bad. Also when they read the codes for the misfire an O2 sensor code P0136 came up as well I was wondering if y'all could tell me where it is located at.