[Shotimes] Help with diagnosis

[Neno Albert]

Performed compression tests yet? No codes? I had a similar problem in three different situations
myself. Bad 02 sensor (causing backfires @ wot), bad wires (just began doing it, was only at WOT
the first week, became more apparent within the week following), and the incorrect spark plug gap.
A sticking valve will cause this as well. I'm kind of old fashioned and still use the trans fluid
trick to help loosen up stuck valves.