I did my own plugs about 2000 miles ago with ngk tr55s and the job came out great. I had no problems. This past week my dad said my car sounded like it was misfiring and at the time i couldnt hear it but i sat behind it and it made a distinct misfire noise at about the same interval. I am guessing it is just one piston. I checked all my connections and noticed plug #2 was loose. I didnt have time to take out my battery so i could fit tools in there to tighten it so i was forced to just retighten it by hand. I got it scanned and i was getting the error "random cylinder misfire".

The car seemed to run fine and i opened it up once and the light came back on. I havent had a time to check the plug again but i wiggled the wire and i think it may be loose again. Does this error code generally imply a spark plug problem or does it seem like an optispark problem.

Edit: I tightened it up and tightened all of the rest of the plugs and checked all the wires on the plug end. I dont see any burnt marks from the top and the wires are routed correctly. I will have to check the bottom end when i get a chance. BTW, when running and looking under the hood, I hear static noise but i see no arcing.

 

ttt