2009 Polaris Sportsman 850 XP EFI EPS Service Manual, Page 61Get this manual
ELECTRONIC FUEL INJECTION TEMPMANIFOLD ABSOLUTE PRESSURE SENSOR (T-MAP)
Operation Overview
Mounted on the (IAFM), the temperature and manifold absolute pressure sensor (T-MAP) performs two functions in one unit
IDLE AIR CONTROL VALVE (IAC)
Operation Overview
The Idle Air Control (IAC) is used to stabilize the idle quality of the engine at cold start-up and after warm-up operations
T-MAP Air passing through the intake is measured by the T-MAP and relayed to the ECUThese signals, comprised of separate air temperature and manifold absolute pressure readings, are processed by the ECU and compared to its programming for determining the fuel and ignition requirements during operation
Mounted in front of the engine, the IAC contains stepper motor which receives varying voltage signal pulses from the ECUThese pulses determine the IAC plunger setting, thereby controlling the amount of air bypassing the closed throttle body for idle controlIf the IAC is disconnected or inoperative, it will remain at it's last operated position