[jakeru]

Checking those timing teeth through the starter hole looks easier than removing the transmission, but still quite hard. I'd suggest marking each tooth you inspect with a marker, to ensure you check them all. Also, suggest looking them very closely because I think in the other thread mentioned, if they're bent by even just 1-2mm or so, it could cause problems. It seems to me that just observing them casually, you might not readily notice if a few are bent only 1-2mm. I also have a hard time envisioning how you'd turn the engine over just a small amount when doing this, to ensure you aren't skipping some teeth - hence, the need to methodically mark them as you verify them OK. Then, you can turn over again and verify they're all marked.

Why do is think it's not worth dropping bent teeth as a possibility? The symptoms seem to indicate the teeth being bent or problematic, and you mentioned you already replaced the sensor. Another way you could verify the teeth being good is potentially by monitoring the crank position sensors's electrical signal, on some sort of appropriate measuring device, like the oscilloscope you mentioned earlier you were familiar with using, but just didn't have ready access to. That would give some confirmation, perhaps more reliably than inspecting through the starter hole, and not require transmission removal.

Sorry to hear you weren't able to quickly figure this out, but I don't think I'd give up just yet!

Best of luck and please continue to let us know if you make any further progress in diagnosing.