Bought a 2004 5AT g35x sedan about two weeks ago. So far I've put about a thousand miles on it and loved it so far until last morning on my way to work i noticed what felt like a misfire. 10 minutes later its missing under throttle (feels really choppy when you get on the gas until about 4k rpms). Check engine light was flashing so I pulled into an autozone to check it out, only code I saw was a misfire in cylinder 5. So I removed the throttle body to clean it up and I noticed a lot of carbon build up so I sprayed that out with some cleaner. Then I noticed i can see light faintly around the bottom edge of the butterfly, is this normal?
Also does this sound like standard operating procedure given the symptoms of the car?
a. clean throttle body and do the idle adjust procedure
b. Switch coils around and see if the misfire follows the potentially bad coil
Thanks for any insight, I really need to get this running right myself because money is really tight at the moment!