FALSE CODE 34 RESET IDLE SPEED

A CODE 34 MAY OCCUR WHEN ENGINE RPM DROPS BELOW A SPECIFIED VALUE, AND THE VACUUM SENSOR OUTPUT IS OUTSIDE A SPECIFIED WINDOW FOR A GIVEN PERIOD OF TIME. THESE VALUES ARE: RPM - 1200 HIGH VACUUM - 68 KPA (20 IN. HG) LOW VACUUM - 17 KPA (5 IN. HG) TIME - 10 SEC. THIS CONDITION USUALLY OCCURS AS IDLE SPEED INCREASES DUE TO LOSS OF GREEN ENGINE FRICTION AND MANIFOLD VACUUM EXCEEDS THE 68 KPA (20 IN. HG) MAXIMUM. WHEN AN ERRONEOUS CODE 34 IS ENCOUNTERED, IT CAN BE CORRECTED BY RESETTING THE IDLE SPEED AS SPECIFIED ON THE EMISSION CONTROL INFORMATION LABEL.

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