380 idles at 1800 rpms in park. Even after setting mechanical idle adjuster to zero this still occurs. What are some likely solutions?

 

SHOULD HAVE AN IDLE AIR MOTOR IN FRONT OF THE AIR FLOW PLATE. 2 PIN CONNECTION. TYPICALLY IF IT IS DISCONNECTED OR IF DEFECTIVE, IDLE WILL GO TO 1500-1800 RPM. i THINK THOUGH THAT IT IS LIKELY THE CONTACT SWITCH ON THE THROTTLE VALVE UNDER THE AIRFLOW PLATE. IT HAS A 3 PIN CONNECTION FOR THERE SHOULD BE CONTINUITY FOR IDLE AT 2 PINS AND CONTINUITY OFF IDLE/POSSIBLY KICKDOWN AT THE OTHERS. I HAD A 380SL AND THE SWITCH WAS THE PROBLEM. THERE ARE ALSO MANY PROBLEMS WITH VACUUM LEAKS BUT YOU WILL SEE A ROUGH IDLE OR ELEVATED TO MAYBE 1000 RPM. THE SWITCH IS ONLY 40-80 DOLLARS BUT A PAIN TO GET TO.