Change plugs, change injector, change Cat and Change OX senor, check compression 165 psi Still can’t get this mis fire engine light problem to go a way.
hmm … well you’ve done a lot already. You must not have too far to go at this point to get rid of that pesky light. I presume this isn’t just a dash light problem, you also notice a performance problem, right?
“misfire” means the engine computer has noticed the crankshaft isn’t accelerating as fast as it should from the explosion inside the cylinder, immediately after a spark plug has supposedly fired. And since it only occurs on number 2, that means it has to be something specific to that particular cylinder. Here’s a couple of ideas
you might not have a good spark a the no 2 spark plug due to a hv wiring problem. visibly check the quality of the spark right at the tip of the spark plug. another idea, look at the engine compartment at night when it is dark to see if you notice any sparks going between hv circuits.
your injector might be ok, but it may not be getting the injector pulse signal from the computer. check for problems,. broken wires, loose connections etc, in the wiring to the injector. it’s not uncommon for the bad connection could be at the injector connector, or back at the ecm connector. measuring the resistance in the wire from the ecm to the no 2 injector might discover something.
A bad cop (coil on plug) or bad crank position sensor are possible.
If you don’t have a performance issue on the vehicle then why don’t you try resetting the code? I’ve done this quite a few times and the light stays off in most instances. The CEL system gets wonky as it ages and is far from perfect.
Bad coil is pretty easy to tell. Look for the bad one most of the time it will look kind of rust colored instead of black like the rest. Have the valves ever been adjusted on this Element? If it has over a 100,000 miles on it they need adjusted. Fairly easy to do for a backyard mechanic. Honda Element owners club have very good precise info on how to do it. The exhaust valves tend to get tight and cause all kinds of symptoms. Does the motor tend to die when first started when it is cold outside is a good sign they need adjusted.
Swap coils with another cylinder.
Swap injectors with another cylinder.
See if the misfire moves.