hi 1991 nissan pulsar1500cc FN14 auto trans RL4-FO3A-FL38 can any one tell me how much transmission oil i need to put in to the above 4 speed auto transmission PLSE THANK YOU

From memory, 4.2L but it depends on how much is still inside the torque converter. Add one litre at a time and keep checking the dip stick to see how much more you need to add to take it to the full mark.