So about a week ago I was playing around and ran through a puddle on my passenger side going about 37- nothing too deep but wide enough to spray water all the way to the driver side. Of course this was right after I was saying how reliable my Disco has been with 134k on her odometer when the service engine light came on and started to run a bit rough. Within about an hour I had the car to my tech and pulled codes - misfire on cylinder 6.

Fast forward:
Replaced all wires and plugs - no dice
Replaced both coil packs - no dice

At this point I am looking at replacing the injector but need some advice and feedback. As far as I am aware - there are no additional codes aside from the misfire on 6. I have been digging through Google and various forum threads which is why I am thinking the injector is next in line. Right now, I feel like I am throwing parts to the problem.

As an aside - I have had a ticking sound for a while now which seems possibly louder now.

 

Wow that's a mystery. I don't know the solution but I'm subscribing so I can learn from the gurus.

I can't imagine what a little water would do to cause a misfire unless it got in the engine or a connector, or maybe caused a short on your spark plug wires, and that should have dried by now anyway. Especially if that is your only code. 6 is on the passenger side and that is where the puddle was so I wonder about your front O2 sensor. . . But if that is your only code I'm stumped as to how a little water could mess up #6. And I sure don't see how an injector could have been affected; the timing of your engine misfire may just be coincidental. I wouldn't replace the injector though. If 6 is still firing at all it should be as simple as replacing the o rings on your injector and if you pull the fuel rail to put a new one in or just fix the #6 injector you would want to replace all of the o rings anyway.

The engine tick could be many things. Have you been able to guesstimate the location (high or low on the engine)? What oil are you using and do you know whether the oil pressure is good? I had some ticking and a switch to Rotella calmed it all down (or masked the true problem; either way it made the engine quiet).

Anyway, I'm floundering. I'll watch and learn, hopefully.

 

I have very rarely replaced injectors. The best option would be to use a oscilloscope on the injector in question. A simple stehoscope on it should also let you know if it is working. Is it for sure getting spark at the plug? Ask your mechanic if the plug is white of black/ dry or wet.


And finally, compression test (super worst case) and the puddle was a coincidence.

 

I had a stuck injector ruin my new engine during break in Bent rod, exploded piston, metal in the oil pump, ruined front cover, scratched fresh turned crank, scratched brand new cam, and new bearings. I'm still not over it. I'll never be over it.