Hi its running MFI

When driving a couple of weeks back it started to lose power but remained running poorly. No smoke or bangs and all fluid are fine.

When opening bonnet it appears there is no power stroke on piston 1 and 2. When removing the plug lead from these it make no diffrence. Pistons 3 and 4 are running fine and pulling these off will stall the engine.

Have checked and swapped plugs and leads around which makes no difference. A spark is jumping the gap between plug and lead on pistons 1 and 2 when the lead is placed close so I think its still getting spark.

Also wouldn't think injectors would fail two at the same time.

Am not sure on whats happened. Most parts are realtivly new and it gets a regular set up once a year. Has to this date ran spot on not missing a beat.

Any ideas would be welcomed as i'm not sure which area to look at