My car's air conditioning system only works part time. After the system runs for a while it stops cooling and warms up in the cabin. Shut off the air for 5 minutes turn it back on cools fine for about 15 minutes then start the process over. Worse on really hot days. Also, heater has stopped working properly. When the car idles, no heat and little heat when the car is moving, worse on very cold days. Also we have developed a leak under the front left part of the engine that only occurs after the engine cools. Does not leak when engine is running. Coolant reservoir has been replaced, still has leak after engine cools.