Ok my parents have just pickd up a utter POS st182 never seen a car so beat up!, its runing soooo cold! it just wont get hot.. the heater is acting as if its a fridge cooler!!!. any ideas no water in the oil or vise versa...
If it is jammed open it will run very cold. But it should warm up when stationary.
If the heater is cold and needle is above quarter you might have blocked heater or heater valve not working.