NO HEAT! and it's freezing outside. SOLVED

Topic: NO HEAT! and it's freezing outside. SOLVED (Read 1685 times) previous topic - next topic

NO HEAT! and it's freezing outside. SOLVED

December 07, 2011, 01:18:43 PM

OK guys. Any help appreciated. New bird, first major issue. It only took a few days in a much colder climate (N. Nevada) to show the weakenesses in my Electronic AC/Heater system in my 87 LX Thundebird. It's been in the teens at night here.

Day One: Everything worked excellent (in California!)

Day Two: Intermittent flashing of LEDs on AC/Heater control with heat taking a long time to come up and never reaching "90" degrees. Not switching between floor, panel, and defrost. Stuck on defrost.

Day Three: Zero heat! Just blowing cold air. Intermittent flashing of LEDs on AC/Heater control. Intermittentently switching between floor, panel, and defrost.

*** Also noticing that when I put the car in PARK there is a noticeable vacuum hiss from under the dash.

NO HEAT! and it's freezing outside. SOLVED

Reply #1 – December 07, 2011, 02:58:31 PM

The vacuum leak in park is probably your automatic parking brake release if you have one. Sometimes the vacuum line comes loose from the brake release.

NO HEAT! and it's freezing outside. SOLVED

Reply #2 – December 07, 2011, 06:26:43 PM

OK, well in my own research for this, I see it's a common problem with the EATC system and that I need to first pull a code from the system per the coolcats tech pages:

http://www.coolcats.net/help/atc.html

And based on my symptoms report above it's probably gonna be a "blend door actuator" problem which unfortunately sounds like a REAL PITA to change out.

If anyone would share they're approach to getting to the "blend door actuator" please inform me. Thanks.

NO HEAT! and it's freezing outside. SOLVED

Reply #3 – December 08, 2011, 03:07:07 AM

I had my eatc act up once or twice while I was driving pizza. Started flashing lights, pulled te code, then it started working fine and never had a problem with it again.

NO HEAT! and it's freezing outside. SOLVED

Reply #4 – December 08, 2011, 10:31:36 PM

This might be a good time for a heated seats mod...

NO HEAT! and it's freezing outside. SOLVED

Reply #5 – December 09, 2011, 12:03:48 AM

Maybe your heater core is also gone chances are if the car is a california car the heater core might be bypassed like it was on my 87 cougar. Common problem for these and also one of the worse heater cores possible to change!! Do you smell coolant at all? I would check the wiring to the heater control unit, might not be making good enough contact or getting enough voltage to work properly. I found all sorts of wires not connected to anything under the dash when I did my heater core and also a spare set of keys from when the car was new.

NO HEAT! and it's freezing outside. SOLVED

Reply #6 – December 09, 2011, 12:25:40 PM

Thanks all. It was the Thermostat. Here's a shot of what it looked like when I took it out, stuck open. I changed it last night. Cabin heat is all back to normal. No more flashing EATC. All blend doors working. Toasty inside and temp gauge is up to 4 bars on the electronic display.

I think the fact that the engine was never reaching normal temp, the "cold engine" override component of the EATC was toggling in and out. Just a guess but seems to make sense. Whatever, it's fixed after staying up to 2:00 am last night in a freezing garage. I enjoyed it.

NO HEAT! and it's freezing outside. SOLVED

Reply #7 – December 09, 2011, 01:33:40 PM

Sweet, love a simple quick fix. The sensor on the heater core tubes will stop the heater from blowing air until coolant is warm. I just unpluggedd mine.