I have a PO302 code showing

Question

Have replaced the spark plug but it came back on what do I check now

Answer 1

check for intake leaks first. What octane fuel are you using? I would use 91 octane from Shell and use a good fuel system cleaner. (maybe do an intake flush since carbon build-up can cause a misfire)

I would swap the coil, and see if the code moves  if that does not help also replace the spark plug wire.