For many parts, you need to measure the oil pressure, check the fuel injector, check the wear of the clutch plate, check the ignition system (spark plug, high voltage line, ignition coil, distributor), check the electronic control system and adjust the ignition timing. Excessive idle speed is related to idle motor, carbon deposit (throttle and idle valve) and electronic control system. Air leakage from throttle body and air intake system can also lead to high idle speed. I suggest you go to Changan Suzuki 4s shop for maintenance. It is not difficult to deal with this kind of fault.
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