The map sensor is a primary reading for idle quality and a bad signal would also cause rough running. It would be rare for the sensor itself to go bad. It could be be dirty, especially if you use an oiled filter like K&N. Clean it with electronics cleaner and a cotton swab but be gentle. 80% of efi problems are wiring. Check the wiring for chafing and broken wires.
Also make sure the vent lines to the fuel tank are not pinched or clogged.
2011 Sportsman 500 HO Touring: Polaris 3500 lb. Winch, Kimpex Adventure XL Trunk, 7" Passenger Foot Risers, UNI Foam Filter
2006 Sportsman 500 X2 EFI: Superwinch Terra 25 w/Synthetic Rope, Kolpin 4 gal Gas Pack, 3" Passenger Foot Risers, 3-Headlight Mod, K&N Filter
SOLD 2010 Sportsman 300: Polaris 2500 lb. Winch, Kolpin Rear Seat (for the dog), UNI Foam Filter
SOLD 2006 Sportsman 700 Twin EFI: 27" Mud-Lite XTR, Superwinch Terra 35 w/Synthetic Rope, Polaris HD Front Springs, OEM Front Bumper Guard, WES Rear Seat, Kimpex Fender Guards w/Footpegs, 3-Headlight Mod, K&N Filter, Symtec Heated Grips
Last edited by AKStew; 05-14-2012 at 10:29 PM.