EGR System Test (Federal)
- Before checking EGR system, ensure throttle position sensor, coolant temperature sensor and pressure sensor are operating correctly. See THROTTLE POSITION (TP) SENSOR, ENGINE COOLANT TEMPERATURE (ECT) SENSOR and MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR under ENGINE SENSORS & SWITCHES
.
- Check for 5th gear switch signal at terminal A5 (Light Blue wire) of ECM. ECM is located behind glove compartment. If voltage is present, check 5th gear switch circuit. See WIRING DIAGRAMS
article.
- To check EGR system, place transmission in Neutral. Apply parking brake. With coolant temperature less than 127°F (53°C), start engine and operate at high RPM. EGR diaphragm should not move.
- Warm engine to normal operating temperature. Operate engine at high RPM. EGR valve diaphragm should retract during acceleration.
- If EGR valve does not operate as specified, check for misrouted, restricted, clogged or deteriorated vacuum hoses. If vacuum hoses are okay, check EGR valve and EGR modulator. See EGR VALVE and EGR MODULATOR/EGR PRESSURE TRANSDUCER.
- If EGR valve and EGR modulator are okay, check EGR Vacuum Switching Valve (VSV). See EGR VACUUM SWITCHING VALVE (VSV).
- If VSV is okay, check for open or short in wiring circuit. See Fig 1
. Check for defective connections at ECM and VSV. If connections are okay, check control relay. See RELAYS
under RELAYS & SOLENOIDS. If all components and wiring are okay, substitute a known-good ECM and recheck.
Courtesy of SUZUKI OF AMERICA CORP.