ok,
2007 polaris sportsman 500......
bike was working fine.
parked in garage for a couple of days...
go to use it and now running like crap. idles fine.
but sputteres and backfires on throttle.
no codes showing while running or idling.

but if i check for codes i am getting a bunch...

22(throttle position sensor, hi or lo)
44 crank position sensor circuit fault
45 map sensor
46 map sensor
55 MIL Circuit load or short to ground
47 IAC stepper motor

i have replaced the wiring harness to the map sensor...
i have unplugged the computer
i have disconnected the battery

codes will not go away...

what the hell?

 

Sounds like my 2006 500 EFI did recently. Battery gave me warnings that it was on its way out. Backfiring, sputtering, surging, stalling. Originally I thought it was bad gas. Didn't solve anything using a good injector cleaner in the gas. Went to go on a trail ride and it was doing it all over again. Hard to start this time like it didn't have quite enough juice. Managed to pull start it and get it back to my truck. Bought a new battery and guy at auto parts place installed it. Ran great for about 23 miles before it got dark and time to go home. Couple weeks later, 20 miles into the ride started acting up again. Buddy suggested checking the screws on the battery terminal. Sure enough they were loose. Tightened them up and it's running like a charm again. I put star washers on and put Loctite on the threads.

 

could be a lack of power where these efi's require 100% voltage to run right. don't know if maybe the ecm might be an issue as well as they controll alot of differnt functions and cause a great deal of weird issues

 

Could be the connector itself on the map sensor harness with possibly a wire or two may have pulled back and not making contact with the map sensor module itself (at least sounds like its in this area since it's sputtering and backfiring) plus have you checked for any bare wires at the crank sensor connector where it rides against the starter,have found shorts there also. OPT