Volkswagen Passat 1995 Official Factory Repair Manual page 2000

Oxygen sensor heater for oxygen sensors behind Three Way
Catalytic Converter (TWC), checking
Mass Air Flow (MAF) sensor, checking
Throttle valve control module, checking
Engine Coolant Temperature (ECT) sensor, checking
Intake Air Temperature (IAT) Sensor, checking
Engine speed (RPM) sensor, checking
Fuel injectors, checking
Fuel pressure regulator and residual pressure, checking
Intake system for leaks (false air), checking
Function tests
Oxygen sensor and oxygen sensor regulation before catalytic
converter, checking
Oxygen sensor and oxygen sensor regulation behind catalytic
converter, checking
Engine Control Module (ECM)
Function
Voltage supply for Engine Control Module (ECM), checking
Engine Control Module (ECM), replacing
Additional signals, checking
Speed signal, checking
26 - Exhaust system, Emission controls
Exhaust system components, removing and installing
Exhaust manifold, front exhaust pipe and catalytic converter with
attachments
Mufflers with mounts
Three Way Catalytic Converter (TWC), checking
Secondary Air Injection (AIR) system
Function
Secondary Air Injection (AIR) system components, removing and
installing
Secondary Air Injection (AIR) system, checking for proper seal
Secondary Air Injection (AIR) valve, checking
Secondary Air Injection (AIR) pump motor, checking
Combination valve, checking