2000 disco
motor rebuilt top hat sleeves 4 years ago and maybe 8k on the motor.
put magnecor wires a year ago with new bosch MAF and new plugs.
Ive gone thru many puddles of water and never had an issue. Well we were at the end trail and I ran thru nice puddle and sure enough my service engine light came on. Starting running really rough intermittently. Final I checked the air cleaner and there was some areas of the filter that were slightly damp but nothing of dripping water. I made it home with intermittent mild loss of power going up some hills. Code that came up was misfire cylinder 4 and general misfire.
As of now I’ve replaced:
MAF( Bosch) sensor
CPS sensor
checked spark plug with tool light seemed fine.
replace plugs just in case.
compression cylinder 4 165psi cylinder 6 168psi
leaked down test of cylinder 4 less 10% cylinder 6 11%

I got new coils(Bosch) but I haven’t install them yet. I’m not sure what else it could be. Fuel injector for number 4?. When I put the new MAF it ran about 45 min before the code came up again. Now it comes up after 5 min. When I do the live data stream on my i930 obd it does show some misfires at idle. When I give it gas the misfire counter pauses. Unfortunately my obd doesn’t specify what cylinder. Any advice would help.
thanks

 

O2 sensors

 

I’ll try to switch those from one side to another. Will faulty sensor just give 1 cylinder misfire? For some reason it’s just giving me cylinder 4.

 

So I switched them unfortunately still misfire cylinder 4.

 

Switch plugs with 6 first, then wires with 3, then coils, then injectors. Known good versus known bad.