Exhaust Controlled Timing (ECT) System
2003 Arctic Cat Snowmobiles
The 500 cc models are equipped with the Exhaust Controlled Timing (ECT) system which utilizes an exhaust pipe temperature sensor. This system automatically adjusts the ignition timing to provide maximum performance through a variety of operating conditions. The CDI unit receives input on engine RPM (demand) and exhaust temperature (engine condition) and adjusts the ignition timing accordingly. This system is not adjustable and is maintenance free.
If a system fault is suspected, use an ohmmeter to check continuity of the exhaust pipe temperature sensor located in the expansion chamber. A reading of either 0 ohm or infinity indicates a failed sensor.
NOTE: A disabled ECT system WILL NOT cause engine damage, however, a failed ECT system will have slower throttle response and may produce slightly less top-end performance.
Updated on: Wednesday, January 27, 2021