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Q: Heater blowing cold air

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Heater will not blow hot air. Have circulation in heater core, diverter gate working, good thermostat. Water disappearing with no leaks found anywhere

Hello. You are likely looking like an internal leak somewhere in the system. If there are no visible leaks inside of the engine bay or visible leaks on the ground, then the engine is consuming the coolant. Have there been any signs of white smoke or steam coming from the vehicle? This is typically caused by a bad head gasket. A 1996 is bound to have issues with a head gasket at some point, specially if it has never been replaced. The poor heater function is likely due to the lack of coolant in the system. The head gasket replacement itself is actually relatively easy, however accessing the head gasket can be an incredible endeavor. It involves removing a number of components from the engine, and reinstalling them correctly afterwards. Long story short, with no external leaks, the engine is likely consuming the oil due to a bad head gasket that will need to be replaced.

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