the engine stalls out for no reason on 1998 Saab 900

recently purchased the car knowin id have to put alittle back into it, however this was unexpected. it starts up fine idles fine, but when you turn the ac on it stalls out, when you put it in gear it stalls out, you can drive it but it randomly stalls. it is automatic so it not operator error. what could be causing this?

Asked by for the 1998 Saab 900
2 answers
poss idle air control system, rec diag and est
could be your lock up solenoid for torque converter have it scanned for codes