I have a misfire on my 2001 XKR with 116k miles. It started obviously misfiring, eventually it went into restricted performance. I pulled the codes and got:

205
305
1316
1642

Since 205 and 305 are cylinder 1B (front drivers side), I went ahead and just replaced that coil. I know that is a poor practice and is "throwing parts at it" but IME it is the coil most of the time and that takes like 5 minutes to do that, so just do it and if that doesn't fix it then do some diagnosis.

For the first time ever replacing the coil did not fix the misfire.

My particular model uses the 4-wire coils and does not have separate ignition modues. So next thing I did was unplug the injector and checked the resistance on the fuel injector for 1B. It read open, I am guessing these should be about 10-15 ohms or so??? So I am thinking that injector is bad.

Looking at it, I think I can pull that injector without taking off the supercharger. If it was any injector other than the first cylinder the entire supercharger and intercooler would need to come off. but it looks like I can get at that particular one without much trouble.

Any comments - either confirmation on the expected resistance and likely culprit being the injector or on the ability to R&R it with the supercharger in place??