very good information, I thank you for your input.

I think we may have the tech check the sprockets, trigger wheels, sensors, and sensor wires.

The tech did say he hears a knock from within the engine, that is why he feels there is internal damage, but we will check the items you listed before replacing an engine.

anyone else have any other possible causes that would trigger 'random misfire' code?

97 Montero SR w/Mitsu Adj Shocks & Rear Diff Lock ARB Front Diff Lock 4.9 Ring/Pinion 3.15 transfer box 43:1 crawl ratio 2" suspen lift 2" body lift 2" Gas Tank Lift 35x12.5 MTRs 15x10 Wheels Rock Sliderz ARB front bumper w/12k winch Custom rear bumper