Heater core replacement on a 1995 Aerostar.

[Jgaryarnold]

Greetings to All: I haven't posted in awhile mostly because my better half has not voiced any criticisms about her van. Well, until now when it's -14 degrees F. here in Louisville, Ky. Her van, scratch that, it's MY van when there is a problem, is a 1995 Aerostar XLT, w/about 135,000 miles on her clock, 3.0 Liter engine, auto transmission w/a front heater/AC assembly only, NO rear heater from the factory. The immediate problem is NO heat coming from the heater. According to her, the heater worked just fine on her way to work, however on the trip home it would not warm up. I first suspected a bad thermostat. So I replaced that, along with flushing the system, & changing the anti-freeze. There was a considerable amount of "gunk" in the cooling system that was flushed out, as well as really nasty looking blackish liquid that I flushed from the radiator & engine as well. There is normal volume of slightly luke warm air blowing through the floor vent when the floor vent position is selected; same thing when selector is in defrost position; however, there is a significantly reduced amount of air flow through the dashboard vents when the selector is in the "Dash Vent Only" position. I'm supposing a possible obstruction in the ductwork maybe could cause this. But I'm even more concerned about the loss of heat situation coming from the heater. I fear I may have a clogged or otherwise faulty heater core on my hands here. Does anyone have any suggestions regarding how to disconnect the apparent "Quick Connect" connections on the heater hoses that connect to the heater core. My view is obstructed a great deal by the AC hoses that run to the firewall, & there is not a lot of extra room to play with. Also, how difficult a job is it to remove the heater core from inside the van? It's been so cold out I have not investigated that far into this project yet. Lastly, I was unaware of this until I test drove the van to begin diagnosis of the heat problem, but the check engine light is also flashing . Any suggestions on this problem? Thanks, Gary.

 

[Jose A.]

sounds like a stuck air-blend door (check under/behind the dash), or a a bad heater valve. I would not even consider the heater Core at this point.

replacement Heater Valves can be found at CarQuest, AutoZone, O'Reilly's, etc. It's a plastic open/close valve, easily replaced. Make sure the vacuum tube is connected to it.

count your blessings that you don't have a Rear Climate System, they are a pain.

 

[BrooklynBay]

Check the vacuum lines under the hood for cracks. The controls are vacuum actuated, so if there's a leak the servo piston & heater control valve can't function properly.

 

[Jgaryarnold]

Thanks Jose A. & Brooklyn Bay. It's beginning to thaw around here slightly, even if only temporarily, so I can get back out & have a look at those areas you've suggested. I/we really appreciate your input. Gary .