1996 Ford Escort hot air heater not working, engine overheating

water blockage, could be thermostat not opening up or the water pump not pumping. probably best not to drive very far, an overheated engine is a danger to itself, also the water pump usually runs off the timing belt, though i know some fords (older fiesta's) have pumps which are directly driven from the engine, in which case, you are in luck, as fixing a water pump running off the timing belt would involve replacing the timing belt, check your model. thermostat, to test it, put some boiling water into a large can then chuck your thermostat in, it should open up if it's working.