Engine knocking

[01 Spectra GT-S]

Ever since I got my car (6months) I've alway been putting in 92 octane gas, just as recommanded. But lately I nocticed that my engine knocks during idle. Should I lower the octane?? or wait until tune up (next month) and let them check it out??

[yota_racer]

You may just need to clean your injectors. Wait for your tune-up though, and go from there. Could be something else.