Ignitor resistance tests are next to useless unless you have a catastrophic failure.
Do whatever you have to do to keep it idling for a few minutes, remove plugs and post a picture of all 4.
A couple friends and I used to wrench some atv's and would run into issues at times.
Now going by the book I never could get resistance readings in line with their numbers for coils and such. According to our manuals the coils were junk and should be tossed. More than once I started to toss an ignition coil based on those numbers but instead checked out other things first and always found the problem which was never the coil.
Maybe those numbers are correct for a new item but I don't think they are reliable for used items. Not in my experience anyway.
i used an oscilloscope to look at my ignition signals and found the pickup signal to be nice and clean. not so much when i look at the igniter to coils. i suspect the igniter. i have cleaned all the connectors twice (all excecpt the back of the fuse box) and can't get rid of the blubbering idle and jumpy tach. the igniter feeds the fi control unit and prob determines when the injectors fire and i would guess a noisy signal would make it run rich, which is what is happening. anybody have a thought about this?
another question: how long should fuel pressure hold in the system after shutdown? mine drops gradually so that overnight it is less than 5psi.
i used my antique (1963) marquette direct connect timing lite using #4 plug and saw a random jumping of the strobe indicating a misfire that jumped about 120 degrees. i'm not sure what it means. i'll try using it on another machine to see if it's the lite.
it starts easy and will idle and will run clean til about 2k rpm to 4k when it starts missing and the tach jumps from about 2k to 4 or 5 while the throttle is held steady. runs strong if you run it hard. but i am going thru spark plugs due to it being rich. all the plugs soot up evenly.