I can think of ywo possible faults: 1. Blocked exhaust.. either baffles moved  or catalyst blocked.. (Warning code) 2. Timing chain has jumped a tooth or several  - so timing is out. (you should get a warning code)   I would start by buying a cheap code reader  or getting someone to read the codes and post them here.   The facts that you have a spark and fuel say it is not igniting for some reason .. - which may/may not be giving a fault code. If it has a yellow lig