Exhaust Gas Recirculation: Testing and Inspection

Using SUZUKI scan tool





1) Connect SUZUKI scan tool to DLC with ignition switch OFF.
2) Start engine.





3) When engine is cool (coolant temperature is below 55°C, 131°F), race engine and check that EGR valve diaphragm is not operating in this state, by touching diaphragm with finger.

CAUTION: If EGR valve is hot, it may be necessary to wear gloves to avoid burning fingers.

4) Warm up engine to normal operating temperature (coolant temperature is above 80°C, 176°F)





5) Turn ON EGR solenoid vacuum valve by using SUZUKI scan tool.

NOTE: Increasing engine speed to higher than 3,000 r/min, driving vehicle or insufficient engine warm-up, will result in interrupting scan tool control.





6) Check to be sure that diaphragm moves toward 1 in the above image above during acceleration and toward 2 during deceleration. If EGR valve fails to operate properly, check vacuum hoses, EGR valve, EGR pressure transducer, EGR solenoid vacuum valve , EGR solenoid vacuum valve (for system check), wire harness and ECM.
7) Keep engine running at idle speed and open EGR valve by hand,
and engine should either stop or reduce its speed. If neither occurs, EGR passage is clogged. Clean it.

Not using SUZUKI scan tool





Different from when using SUZUKI scan tool described previously, it is necessary to input vehicle speed to ECM to cause EGR valve to operate. When checking operation of EGR valve, hoist vehicle, start engine, release parking brake lever and check that rear propeller shaft (rear wheels) is turning. If not, perform following check with one rear tire locked and the other turned by hand.

WARNING:
Make sure that M/T or A/T is set to "Neutral" position for this check. If it is set to any other position, rear tires will turn at high speed and a very dangerous situation may occur.