Ok so the more we look into it, the more it looks like all this was caused by the failed injector. Also contacted Emann, the man himself. He thinks the injector is the most probable scenario, given that these injectors tend to fail a lot. Cylinder 4 run lean and here we go. Weird part is that while I heard the banging for some time, it threw the code only when it was too late.
Its interesting about the injector, ive been getting supplies ready for the big service on my dads crv as its coming up on 30k soon and looking through the manual it says use genuine honda injector cleaner every 10k km, didnt even know about that, have u used it at all before?
that is the absolutely the first time I hear of this. I did not know there actually is "genuine Honda injector cleaner"....although I do not see how it can help if you run good gas....does it have a part number, this injector cleaner?!