96 windstar rear heater blowing cold

[thager]

im my 96 windstar my rear heater alwase blows cold ,could this be a plugged line or heater core??

[vindctar]

As you know, in the 1996 model year, rear heater vents are located on the left wall, close to floor. So, you say that these vents are blowing cold air in your car. Correct? Are you getting heat in the front or not? If no heat in the front either, then one possibility is that the thermostat is stuck in closed position. If there is heat in the front, then I think hot coolant is not reaching the rear heater core or somebody has disconnecetd the line that takes coolant to the rear heater core; some people would do this if the rear heater core develops a leak. If the coolant line has been detoured to bypass the rear core, you should be able to see this under the car.

[thager]

ok , i get good heat from the dash vents but the rear is cold even the roof vents for the rear are cold ,ill check the lines when i get time .

[Flyingjackal456]

For the rear Heat/AC system the hot air is supposed to come out through the floor vent (right next to feet if sitting in middle bench, driver side), and the AC or vent (cold) air is supposed to come out through the wall and roof vents.

Easy check, When the engine is cold, check your coolant level, this sounds to me like a classic, low coolant thing. If you haven't changed your coolant in a while, I'd suggest changing it. If you never changed it since new, you may have clogs in the radiator and heater core, due to the OEM coolant had a high silica content, which made sand-like clumps if left in the car too long. I had to blast air through my overflow tank line to clear the sand clumps from it. (The rest of my cooling system is brand new )

[adrenochrome]

Make sure the cooling tank is full to the mark as mentioned and refill as nesassary... After the van has been warmed up to operation temp, you should be able to feel the upper radiator hose to see if you got a stuck closed thermostat... If the hose is really hot then it's working, if not, bad thermostat... I would just say replace the thermostat anyways but it's looks like a pretty tough job all for putting an aftermarket crap thermostat, avaialble at these parts stores. So with that outta the way and im sure it still doesn't work, underneath the van, behind the drivers side rear tire you should see about 4 lines going to the rear unit (hopefully connected)... With van still running and rear heater turned on, 2 of those lines are heater lines and they are a bit bigger than the 2 smaller A/C lines and they should be pretty hot to the touch... If they're hot, then it's probably a rear blend door problem perhaps a busted vaccum line or actuator, if those lines are not hot, im sure it's a heater control valve issue which again is vaccum operated and could be a busted line or valve... Clogged line is doubtful but could be checked by feeling one line at a time all they way up to the front feeling for hot and cold spots.

[vindctar]

In 1996 Windstar, there is no blend door for the rear heater/AC. I believe, thermostat is fine because he's getting heat from the dash vents.

[Flyingjackal456]

no blend door in 1998 WS either, it's more like an open/closed door, it doesn't blend at all, just switches from top vents and bottom vents. It definitely sounds like low coolant to me, I've had this issue in both my 1998 and my 2002 windstars.