2001 Saab 9-3 Owner's Manual - Page 195

Car care Saab Trionic engine management system The Saab Trionic engine management system is a unique Saab development that combines sequential multiport fuel injection, electronic distributorless ignition and turbocharger boost pressure control into one system. The Trionic engine control module (ECM) monitors many different engine parameters such as: • Intake manifold pressure. • Intake air temperature. • Crankshaft position. • Engine coolant temperature. • Throttle position. • The oxygen content of the exhaust gases. The ECM receives information regarding engine knocking from a sophisticated feedback function in the ignition discharge unit. By processing all of this information, the Trionic system can control fuel injector opening duration, ignition timing and turbocharger boost pressure to provide excellent engine performance while maintaining low emissions and fuel consumption. 195 NOTE The Trionic engine management system continuously monitors the operation of these systems and has on-board diagnostic capabilities (OBD II). If the CHECK ENGINE light in the main instrument illuminates, the Trionic ECM has detected a problem. The car will continue to operate, but performance may be diminished. You should have your car checked by a Saab dealer as soon as possible. ORVR (Onboard Refueling Vapor Recovery) All hydrocarbons formed when refueling will be recovered by the car and not released into the atmosphere. The hydrocarbons are absorbed in an evaporative emission canister. When the engine is subsequently started, the evaporative emission canister is gradually purged as air is sucked into it through a shut-off valve. The hydrocarbon/air mixture passes through the evap canister purge valve and into the engine where it is burned. "Refueling", see page 157.