Sounds like a tstat to me also.

itsnotmeitsyou wrote:

Water will circulate through the radiator with the thermostat closed but it won't get any heat from the engine, so no hot air
Sounds like the thermostat is only partially working, otherwise the engine would have melted down.
Hopefully you didn't warp you heads.

Heat for the cabin does not come from the radiator, it comes from the heater core which is not impacted by the tstat. Coolant circulates because of the water pump, the rad and hoses are out of the loop when the tstat is closed, but none of that matters to getting heat into the cabin.

Sounds to me like you have air in the system, especially if you replaced the condenser recently I would think you had to get the rad out of the way for that job. Get the front end up in the air and burp the system.

I've done the coolant flush (and a t-stat replacement once during the timing belt service) a couple of times on my own car, and this is the process I follow on a COLD car:

1.) Remove lower radiator hose from radiator, allow to drain as much as possible, and capture as much coolant as you can (for recycling). Using the radiator hose to direct the coolant is much less messy than using the drain on the radiator.
2.) Remove the lower hose from the t-stat housing, then the housing itself and the t-stat. Clean the mating surfaces well and use a new gasket. In my previous experience, the gasket is sourced separate from the t-stat. Re-install both, and thoroughly clean the t-stat housing and radiator necks to remove crusty coolant and corrosion on the aluminum. Put the hose back on with new clamps.
3.) Remove the radiator and turbo coolant reservoir caps. Refill the radiator and overflow bottle (to the MAX line). Reinstall the radiator cap.
4.) Top off the turbo coolant reservoir. Leave the cap off.
5.) Start the car and set the ACC to max heat, recirculation OFF
6.) Add coolant to the turbo reservoir as possible. It will more or less drain the entire thing on startup, keep it full as the car warms up. Once no more bubbles appear, you're done.

Remember that you always leave the highest point of a cooling system open when burping. Fluid will flow with gravity, bubbles will float up to it. Any trapped air in the radiator will find their way out through the overflow bottle or the long way out through the turbo reservoir.

In addition, you never want to work on a hot cooling system, unless you have no alternative (i.e. broken down).

Typically, I would call it good if it stopped taking coolant at the turbo tank, and a check of a cool car (at least 12h cooling time) reveals the tank to still be full.

The bubbles will consolidate somewhere in the engine, and driving will push what little air will be left out the radiator (into the overflow) or to the turbo tank.

Yeah, the fans run. I did forget to plug them back in at first, but I quickly realized that mistake when I was filling the A/C and they didn't turn on.

I just did the replacement of the thermostat and a very careful refill of coolant per Krazy's recommendation.

I did a test drive and it did fine. That doesn't mean much, since it overheated about 2 weeks after the last time I refilled it, so, I'll still be watching it closely for a while.

92XAERO87 wrote:

dotMaster I went through all these steps a few months back. There is a Coolant sensor located on the top of the block under the alternator.

This tells the computer in the car when to engage the fans, pump more coolant etc. I was noticing my fans would only engage for when my AC compressor was on and that without proper flow the car would overheat.

All the above are great recommendations but this 20 dollar sensor is also a critical part to eliminating the issue,

http://shop.advanceautoparts.com/p/carq … emp+sensor

Thanks for the heads up on that. I'm pretty sure my coolant sensor is good, though, because the fans do kick after 10 minutes of idling or so. That seems to be operating correctly. I'll keep an eye on it, though.

Also, I'm pretty sure the issue was not the thermostat. I tested it in water on the stove and it opened right up. I think I just screwed up the fill last time and somehow the air pocket layed dormant until this past Saturday. Anyway, here's hoping that's the end of it.

As a last note: I got towed through AAA 67 miles on Saturday. I have a basic membership, so it would have cost ~$385 since basic only covers 7 miles of towing. On the tow driver's recommendations, I called AAA while literally riding home in his truck and upgraded to the Plus membership for $144. That covers 100 miles of towing, so I paid nothing for the tow and saved a little over $200. So, just know that if you're ever in a similar spot. No reason to upgrade to Plus until you need it.

Wouldn't I have seen a bunch of coolant around the caps if that was the case though?

I have seen Subarus diagnosed with failed head gaskets when it was only a rad cap no longer holding the necessary pressure in the system. Remember that the cap is the pressure relief valve for the system, so if it is no longer holding pressure properly, the car will bleed coolant into the overflow when hot and suck it dry as it cools... Meaning that if the car's cap has failed, the potential to draw air into the system is possible.