i was wondering if some could help? I have 07 G35X. I replace spark plugs because mis fire in cylinder number 1 and was getting 0301 code. After i replace plugs still had problem. I switched coil packs and still have the same problem in number one cylinder and my 0301 code.I also took coil pack with old plug and grounded it out while runing the car and if was firing. The car has 79 thousand miles on it. Any ideas?

 

Perhaps there is a problem with the fuel injector for that cylinder? Did you happen to check that?