Check the firewall (engine bay side) for a small rubber tube extending forward....it's the drain for your A/C. When the A/C cools the air, it condenses moisture on the coils. The drain tube sometimes gets blocked with dust and/or road grime. Work a small wire up into the tube, and chances are, you'll get a gush of water from it.
You just have low coolant in the cooling system. When the level gets low there will be air in the system and air in the heater core. When there is air in the heater core, you will hear this water rushing noise as coolant flows in the heater core in the dash. The first thing you'll need to do is check the coolant level. This is surely what the problem is. With the engine cool remove the radiator cap, and you should find whether it is low. If so, check for leaks. The water pump is a very common leak on these, and the radiators can leak too, along with the normal things like the heater hoses and radiator hoses. If you have rear heat, there are lines at the firewall and under the van on the right side that can leak. Once you have found the leak, or if you can't find a leak, you need to bleed the system.
sounds like rain may have leaked into the duct which supplies hot/cold air flow.check that first only thing that is behind your dash and connects to both left /right sides and could hold water.
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Check the firewall (engine bay side) for a small rubber tube extending forward....it's the drain for your A/C. When the A/C cools the air, it condenses moisture on the coils. The drain tube sometimes gets blocked with dust and/or road grime. Work a small wire up into the tube, and chances are, you'll get a gush of water from it.
You just have low coolant in the cooling system. When the level gets low there will be air in the system and air in the heater core. When there is air in the heater core, you will hear this water rushing noise as coolant flows in the heater core in the dash. The first thing you'll need to do is check the coolant level. This is surely what the problem is. With the engine cool remove the radiator cap, and you should find whether it is low. If so, check for leaks. The water pump is a very common leak on these, and the radiators can leak too, along with the normal things like the heater hoses and radiator hoses. If you have rear heat, there are lines at the firewall and under the van on the right side that can leak. Once you have found the leak, or if you can't find a leak, you need to bleed the system.
sounds like rain may have leaked into the duct which supplies hot/cold air flow.check that first only thing that is behind your dash and connects to both left /right sides and could hold water.