No heat in 93 Impreza

[Murthius]

Hi, I know this thread is sliiiightly redundant, I've read all the others related to it but the others have some different symptoms and outcomes than my situation. My 1993 Impreza LS Auto AWD Sedan has no heat. The A/C works great, and the air blows like a mofo, but no heat at all. I've done the methods in other threads to try to fix it, I got a new Subaru T-stat and gasket, flushed the system, burped the system, all that. But still no heat. Is it time to declair heater core as the problem? Give up and take it to a shop? Or is there something I'm missing? Thanks for any info.

[98obster]

here's my thought, I don't button up a flush job until I feel heat coming out of the vents. Did you have the heater going while you were filling and burping. I suspect you have air in the heater core. you sometimes have to really raise the front end to get the air out. drain cooland and then refill from heater core inlet hose to force air out.

[Murthius]

Yeah I had the dials set to heat with the fan on full blast, left the cap off while running the car up to operating temp and slightly reving the engine and pouring more 50/50 in every time some air bubbles came out and the level went down until no more bubbles came up, took a good 20 minutes or so. Didn't raise the front end though since all I have is my cheap little jack and no jack stands lol. Raising the front end was probably a big part of the process and leave it to me to leave it out huh? [Edit] How much should I raise the front end?

 

Also the flush I got was PEAK and it was in a far smaller bottle than the Prestone one I saw in other threads, the auto parts store near me didn't have the Prestone one, and I'm wondering if I should go out a bit farther to another one that might have it, or should I not worry too much about that?

 

Thanks.

[lmdew]

Is the temp control cable moving the vent flap? The cables gears break in these often. Check on the passenger side up under the dash as you move the temp control, make sure the cable is moving the flap.

 

On the heater core, just feel the hoses in and out of the firewall. If they are both about the same temperature and warm, you have flow through the core.

[Allpar Mod]

Air in the system seems to be a common problem with Soobs when the systems are flushed. Since you say you corrected this, we'll look elsewhere, though I would double check this as you possibly still could have air trapped in the system.

 

Before I'd start tearing into the heater core, I'd check the heater control valve. If this is stuck closed, you'd get no coolant flow through the heater core. This should be inline of the heater hose coming off the water pump. If you used a/c over the warm months, the slide switch would have been in the blue, therefore, the heater control valve shut. If a malfunction in the actuator or the valve itself occurred during this time, it will still be in the shut position internally.

[subsince77]

Last winter the cable housing came out of the cable housing stop on the back of my control unit (in dash) in my 97 OBW. When I would move the lever to heat, the cable housing was not held in place, so it would just flex and not move the actual lever on the heater core.

 

It was way too cold to fix it, I was afraid I would break some plastic parts removing the control unit in below zero weather. So, for the winter I just pushed the lever by hand and blocked it in place with something. I had loads of heat. Then in the summer, I took it apart and glued the cable housing back into the cable housing stop.

 

That's my story. Maybe it will help.