holgisbest

Engine started loosing all power under 1600 revs during the last 500 miles. Giving me codes of random misfiring or misfiring of different cylinders No driveability any more. timing chain changed at 100k. All sensors exept HO1 sensor 2 (right downstream, heater circuit malfunction which should not influence fuel/air mix) show "no fault". MAF, TPS, VCT, IMRC, COP's etc. all ok. No overheating, no oil spill or coolant loss. Spark plugs all @ 1,1ms, injectors clean, apparently no vacuum leak in intake manifold. Live data show nothing out of normal.This morning misfiring it blew my muffler apart trying to start it up. Anyone any idea?
Will check compression tomorrow, maybe onee valve stuck open. I'll update on that. Exhaust is defenitely not plugged after that explosion blowing up the muffler. Former owner had eliminated the cat's anyway.