ENGINE EG169 EXHAUST GAS RECIRCULATION (EGR) SYSTEM (California only)
EG170 ENGINE To reduce NOx emissions, part of the exhaust gases are recirculated through the EGR valve to the intake manifold to lower the maximum combustion temperature. ect Below 47 C (117 F) Above 53 C (127 F) RPM Below 4,000 rpm vsv.... OFF ON Throttle Position Below port E Between port E and port R Above port R Pressure in the EGR Valve Pressure Chamber (1) LOW (2) HIGH (3) HIGH Pressure constantly alternating between low and high EGR Vacuum Modulator OPENS passage to atmosphere CLOSES passage to atmosphere CLOSES passage to atmosphere EGR Valve CLOSED CLOSED Exhaust Gas Not recirculated Not CLOSED recirculated Not CLOSED recirculated OPEN OPEN Not recirculated Recirculated Recirculated (increase) Above 4,400 rpm (4) OFF CLOSED Not recirculated * * When the throttle valve is positioned above port R, the EGR vacuum modulator will close the atmosphere passage and open the EGR valve to increase the exhaust gas, even if the exhaust pressure is insufficiently low. * * * VSV switched ON when product of engine speed multiplied by vacuum sensor valve exceeds a specified valve. * * * * If terminals TE 1 and E 1 of data link connector 1 are connected, the VSV switches ON. EGR SYSTEM INSPECTION 1. INSPECT AND CLEAN FILTER IN EGR VACUUM MODULATOR (a) Remove the cap and filter. (b) Check the filter for contamination or damage. (c) Using compressed air, clean the filter. (d) Reinstall the filter and cap. HINT: Install the filter with the coarser surface facing the atmospheric side (outward). 2. INSTALL VACUUM GAUGE Using a 3way connector, connect a vacuum gauge to the hose between the EGR valve and EGR vacuum modulator. 3. INSPECT SEATING OF EGR VALVE Start the engine and check that the engine starts ane runs at idle.
ENGINE EG171 4. CONNECT TERMINALS TE1 AND E1 OF DATA LINK CONNECTOR I Using SST, connect terminals TE1 and E1 of the data link connector 1. SST 0984318020 5. INSPECT VSV OPERATION WITH COLD ENGINE (a) The engine coolant temperature should be below 47 C (117 F). (b) Check that the vacuum gauge indicates zero at 2,500 rpm. 6. INSPECT OPERATION OF VSV AND EGR VACUUM MODULATOR WITH HOT ENGINE (a) Warm up the engine to above 53 C (127 F). (b) Check that the vacuum gauge indicates low vacuum at 2,500 rpm. 7. REMOVE VACUUM GAUGE Remove the vacuum gauge, and reconnect the vacuum hoses to the proper locations. 8. INSPECT EGR VALVE (a) Apply vacuum directly to the EGR valve with the engine idling. (b) Check that the engine runs rough or dies. (c) Reconnect the vacuum hoses to the proper locations. 9. REMOVE SST FROM DATA LINK CONNECTOR 1 SST 0984318020 IF NO PROBLEM IS FOUND WITH THIS INSPECTION, SYSTEM IS NORMAL; OTHERWISE INSPECT EACH PART
EG172 ENGINE VSV INSPECTION 7. REMOVE VSV 2. INSPECT VSV A. Inspect VSV for open circuit Using an ohmmeter, check that there is continuity between the terminals. Resistance (Cold): 3744 If there is no continuity, replace the VSV. B. Inspect VSV for ground Using an ohmmeter, check that there is no continuity between each terminal and the body. If there is continuity, replace the VSV. C. Inspect VSV operation (a) Check that the air flows from port E to the filter. (b) Apply battery voltage across the terminals. (c) Check that the air does not flows from port E to the filter. If operation is not as specified, replace the VSV. 3. REINSTALL YSV
ENGINE EG173 EGR VACUUM MODULATOR INSPECTION INSPECT EGR VACUUM MODULATOR OPERATION (a) Disconnect the vacuum hoses from ports P, Q and R of the EGR vacuum modulator. (b) Block ports P and R with your finger. (c) Blow air into port Q, and check that the air passes through to the air filter side freely. (d) Start the engine, and maintain speed at 2,500 rpm. (e) Repeat the above test. Check that there is a strong resistance to air flow. (f) Reconnect the vacuum hoses to the proper locations. COMPONENTS FOR EGR VALVE REMOVAL AND INSTALLATION
EG174 ENGINE EGR VALVE REMOVAL (See Components EGR valve for Removal and Installation) 1. DISCONNECT NEGATIVE TERMINAL CABLE FROM BATTERY CAUTION: Work must be started after 90 seconds from the time the ignition switch is truned to the LOCK position and the negative () terminari cabie is disconnceted from the battery. 2. REMOVE AIR CLEANER HOSE AND CAP (a) Disconnect the IAT sensor connector. (b) Loosen the air cleaner hose clamp bolt. (c) Disconnect the four air cleaner cap clips. (d) Disconnect the air cleaner hose from the throttle body, and remove the air cleaner cap together with the air cleaner hose. 3. DISCONNECT ACCELERATOR CABLE BRACKET FROM THROTTLE BODY (a) Disconnect the accelerator cable from the throttle linkage. (b) A/T: Disconnect the throttle cable from the throttlelin kage. (c) Remove the 2 bolts and cable bracket. 4. DISCONNECT THROTTLE BODY FROM AIR INTAKE CHAMBER (a) Disconnect the 2 EGR vacuum hoses. (b) Disconnect the EVAP vacuum hose. (c) Disconnect the TP sensor connector. (d) Disconnect the IAC valve connector. (e) Remove the 2 bolts and 2 nuts, and disconnect the throttle body from the air intake chamber. (f) Remove the throttle body gasket.
ENGINE EG175 5. REMOVE ENGINE HANGER, AIR INTAKE CHAMBER STAY AND EGR VACUUM MODULATOR (a) Disconnect the EGR hose and vacuum hose from the EGR valve. (b) Remove the 2 bolts, and disconnect the air pipe and fuel inlethose. (c) Remove the bolt, nut, engine hanger, air intake chamber stay, EGR vacuum modulator and gasket. 6. REMOVE EGR VALVE AND PIPE (a) Loosen the union nut of the EGR pipe. (b) Diconnect the vacuum hose from the EGR valve. (c) Disconnect the EGR gas temperature sensor connector. (d) Remove the 4 nuts, EGR valve and pipe. (e) Remove the 2 gaskets.
EG176 ENGINE EGR VALVE INSPECTION INSPECT EGR VALVE Check for sticking and heavy carbon deposits. If a problem is found, replace the valve. EGR VALVE INSTALLATION (See Components EGR valve for Removal and Installation) 1. INSTALL EGR VALVE AND PIPE (a) Install a new gasket to the cylinder head, facing the protrusion downward. (b) Install a new gasket to the EGR valve and pipe with the 4 nuts. Torque: 13 Nm (130 kgfcm, 9 ftlbf) (c) Connect the EGR gas temperature sensor connector. (d) Connect the vacuum hose to the EGR valve. (e) Tight the union nut of the EGR valve. Torque: 59 Nm (600 kgfcm, 43 ftlbf) 2. INSTALL AIR INTAKE CHAMBER STAY, EGR VACUUM MODULATOR AND ENGINE HANGER (a) Place a new gasket to the intake manifold, facing the protrusion downward.
ENGINE EG177 (b) Install the air intake chamber stay, EGR vacuum modulator and engine hanger with a new bolt and the nut. Torque: 28 Nm (290 kgfcm, 21 ftibf) (c) Connect the air pipe and fuel inlet hose with the 2 bolts. (d) Connect the EGR hose and vacuum hose to the EGR valve. 3. INSTALL THROTTLE BODY (a) install a new gasket on the air intake chamber stay, facing the protrusion downward. (b) Install the throttle body with the 2 bolts and 2 nuts in the sequence shown. Torque: 22 Nm (220 kgfcm. 16 ftbf) (c) Connect the IAC valve connector. (d) Connect the TP sensor connector. (e) Connect the EVAP vacuum hose. (f) Connect the 2 EGR vacuum hoses.
EG178 ENGINE 4. CONNECT ACCELERATOR CABLE BRACKET TO THROTTLE BODY (a) Install the cable bracket with the 2 bolts. Torque: 11 Nm (115 kgfcm, 8 ftibf) (b) A/T: Connect the throttle cable to the throttle linkage. (c) Connect the accelerator cable to the throttle linkage. 5. INSTALL AIR CLEANER HOSE AND CAP (a) Connect the air cleaner hose to the throttle body. (b) Install the air cleaner cap together with the air cleaner hose. (c) Connect the IAT sensor connector. 6. CONNECT NEGATIVE TERMINAL CABLE TO BATTERY