will not idle on 1990 Dodge Spirit

the car will start fine but will not idle. it dies after stating up unless i feather the heck out of the throttle. the fuel pump and sock, fuel filter, timing belt, idle air control motor and idle postion sensor have been changed. it shows codes 12 and 55 only. HELP

Asked by for the 1990 Dodge Spirit
those are normal codes. code 12 is no tach signal but you checked it with the motor off. 55 is end of check.
i would look for a vacuum leak for the idle. also, check the map sensor. the line clogging up with carbon was common.

line is not clogged and no leak. thanks anyway
what did you set the minimum authority screw at??

sorry but what minimum authority screw