DME 7.8 DME 7.8 0 · 0-P0446P0446

DME 7.8 DME 7.8 0 0-P0446P0446 EVAP canister shutoff valve (function) - below limit Diagnosis conditions • Oxygen sensing system active • No secondary air diagnosis • Engine running • Vehicle speed = 0 km/h • Intake air temperature between 5 °C and 50 °C • Engine starting temperature between 5 °C and 55 °C • Battery positive voltage greater than 11 V • Engine load less than 30% • EVAP canister burden less than 3 • Altitude correction factor greater than 0.75 • Time elapsed after engine start-up > 990 seconds (16.5 min- utes) or mixture adaptation completed • No fault for throttle position sensor, idle air control, vehicle speed, EVAP canister purge valve, mass air flow sensor, voltage supply, pressure sensor, shutoff valve or engine temperature in memory Note! Fuel tank ventilation diagnosis is initiated with the Porsche System Tester 2 in the "Short test" menu. This reduces the time elapsed after engine start-up to 30 seconds. Possible fault cause ♦Purge air line blocked ♦EVAP canister purge valve sticks in the opened position (this causes continuous vacuum to go from the intake manifold to the tank system) ♦EVAP canister shutoff valve is blocked/sticks in the opened posi- tion ♦Flow resistance of EVAP canister too high (filter deformed/ blocked) ♦Pressure sensor connected incorrectly (polarity reversal) 2093 P0446 0-P0446 page 1 Printed in Germany – 13, 2003 p0446