Category: Fuel & Emissions

Throttle Body Description The throttle body is of the single-barrel side-draft type. The lower portion of the throttle valve is heated by engine coolant which is fed from the cylinder head. The idle adjusting screw which increases/decreases bypass air and the evaporative emission (EVAP) control canister port are located on the top of the throttle […]

Idle Control System Troubleshooting Flowchart A/T Shift Position Signal This signals the PGM-FI ECU when the transmission is in Neutral or Park. Inspection of A/T Shift Position Signal. Turn the ignition switch ON. Observe the A/T shift indicator and select each position separately. See A/T Shift Position Indicator Inspection.Does the indicator light properly? Turn the […]

Fuel Supply System PGM-FI Main Relay (cont’d) Troubleshooting Flowchart (To page 11-123) BLK/ WHT GRN/ YEL/ BLK PGM-FI MAIN RELAY BLK/ YELBLK YEL/ BLU BLK/ YEL BLK/ YEL BLK Engine will not start. Inspection of PGM-FI main relay. Disconnect the PGM-FI main relay connectors. Check for continuity between BLK terminal and body ground. Does continuity […]

Fuel Supply System PGM-FI Main Relay Troubleshooting Is there continuity? Check for an open or short in the wire: Measure voltage between the PGM-FI main relay 4P connector terminal No. 3 and body ground. Is there battery voltage? Check for an open or short in the wire: 1. Turn the ignition switch ON (II). 2. […]

Fuel Injection Air (FIA) Control System Description The Fuel Injection Air (FIA) Control system enables fresh air to be drawn through the throttle body and fuel injector port. IDLE ADJUSTING SCREW THROTTLE BODY FUEL INJECTOR AIR FLOW Attachments nsxb11153a (56 kB)

Three Way Catalytic Converter (TWC) Description The Three Way Catalytic Converter (TWC) is used to convert hydrocarbons (HC), carbon monoxide (CO), and oxides of nitrogen (NOx) in the exhaust gas to carbon dioxide (CO2), dinitrogen (Nz) and water vapor. SECONDARY HEATED OXYGEN SENSOR (SENSOR 2) THREE WAY CATALYST HOUSING Attachments nsxb11159a (52 kB)

Intake Air System Description The throttle valve dashpot is employed to slow the closing of the throttle valve during gear shifting or deceleration. THROTTLE VALVE DASHPOT CONTROL DIAPHRAGM THROTTLE VALVE DASHPOT CHECK VALVE Throttle Valve Dashpot System Attachments nsxd11134a (163 kB)

Emission Control System The emission control system includes a Three Way Catalytic Converter, Exhaust Gas Recirculation (EGR) system, Positive Crankcase Ventilation (PCV) system and Evaporative Emission (EVAP) control system. The emission control system is designed to meet federal and state emission standards. Tailpipe Emission 1. Starting the engine and warm it up to normal operating […]

Fuel Supply System Replacement Fuel Tank Do not smoke while working on fuel system. Keep open flame away from your work area. Make sure lifts are placed properly (see page 1-9). 1. Raise the car. 2. Remove the drain bolt and drain the fuel into an approved container. 3. Remove the center rod (see section […]

System Description Vacuum Connections CONTROL BOX page 11-8 EVAP PURGE FLOW SWITCH INTAKE AIR BYPASS (IAB) DIAPHRAGM FUEL PRESSURE REGULATOR EVAP PURGE CONTROL DIAPHRAGM VALVE EVAP CONTROL CANISTER FRONT OF VEHICLE EGR VALVE LIFT SENSOR To EVAP TWO-WAY VALVE EGR VALVE System Description Vacuum Connections (cont’d) Control Box EVAPORATIVE EMISSION (EVAP) PURGE CONTROL SOLENOID VALVE […]