Error code P0303, #3 engine misfire
So I know that Cylinder #3 is misfire. I just recently replaced the plugs with the autolite iridiums, and the air cleaner. Ran awesome for few days, then it started to have a very rough idle at a stop. I tried to remove the plug, look at it and reinstall it, same issue, same cylinder. So I bought another plug, just to try and see if this fixed the problem, then I was going to check the coils by switching them, plugs were in store, Coils is special order. I first tried the spark plug and surprisingly it fixed the problem. So it must be a bad plug (New one), right? I mean, when a coil goes bad, can it send to much charge to the plug and ruin them? I know this may be a stupid question, but just wanted to ask before I purchase 6 coils, might as well do all if I do them. I have a long trip planne this Sat, so ......
Thanks for your replys