2009 Sportsman 550 EFI turns over, has 37 PSI of fuel pressure, has spark although it look sporadic rather than timed. It fires and chugs but wont start. It also wont start with a shot of ether. I believe the fuel pressure is supposed to be 43/44 so its a bit under spec but I would think with the fuel pressure it has and the ether that it would try to run. I believe the flywheel magnets are sealed on these new Sportsmans. I know the older ones had issues with the magnets shifting or coming off.

any ideas would be wonderful

 

Hi.
No idea on the fuel pressure.
You could have anything from a bad pickup coil to bad ecu/cdi to a bad connection. At the moment with the description given it could be allot of things but sporadic fire at the plugs points to ignition problems.
Battery fully charged? If not that will give you a weak spark and low fuel pressure.

 

So i was able to swap the ECU and the coil with another "running" 2009 Sportsman 550. Still have a no start issue. checked the pick up coil resistance and got 194.7ohms on the running unit and 197.6 on the no running so it appears the pick up coil is good. Checked the stator resistance and 4 ohms average on the running unit and 5 ohms average on the none running unit so again I would say the stator is good. Only thing left is checking the voltage regular. I have a known good unit I with swap tomorrow, If that's not the issue then im at a complete loss. Does the odometer play any role in engine operation? I know on some of the carbureted units it does.

 

Try unhooking the black kill switch wire. Kill switch turned to off?

 

swapped in good regulator. No Change. Pulled stator out to make sure flywheel didn't spin on the crank and shear the woodruff key. All is good with that.

 

Run a compression check to see if cylinder is good, but will also show if valve timming is good

 

Already checked timing and compression

 

Man you might need to take it to a dealer repair shop. Electrical problems are the number one hardest to diagnose over the internet and sometimes even when your right there looking at it.
Sorry i can't be more help to you but please let us know when you get it fixed what the problem was so in the future it might help others.