Hi all, I’m curious. My 6 cylinder Nissan Altima 2013 3.5 SL had the check engine light come on the other day, so today my brother came over and we used his reader, it said there was a cylinder misfire. So we popped the hood and started to check the 3 spark plugs we could access in the front part of the engine, we disconnected the battery while doing this. We realized we might need a shop as we don’t know what we’re doing to reach the other 3 spark plugs. That being said we put it all back together and then started the car and the check engine light was gone. We drove for a good while, and everything seems fine. What happened? Am I in the clear? Or do I still need to take it in?

Thank you so much in advance.