I have a 95 Accord EXL and the heater is not working. The engine heats up normally, the blower blows, the temperature dial turns, but no heat. The AC is not very cool, I recharged it this summer and that helped some, but not much. I don't know if that has anything to do with the heater. Where should I start looking for the cause of the heater problem?

Thanks
Richard
95 Accord EXL 2.2 L SOHC 4-Cyl 16-Valve, 4-speed auto transmission

 

The temperature control **** in your car tightens a cable that goes to the heater core. See if changing the temperature in the car changes the position of the heater core valve (you may want to get a partner to help you). If no movement, then spray the valve with PB blaster to lubricate, since it may be rusted.

I have also read where the control **** in the car can be cracked on the plastic shaft, and not really do anything when you turn it.

To locate the heater control valve, look in the engine bay on the passenger side near the firewall. The control valve attached to one of the hoses entering the cabin. #1 in the diagram.

 

Thanks for the reply. The cable does move the heater core valve.

 

I'm not sure about 95, but later (at least by 98) that cable is motorized. You need to turn the key on when you check for cable movement.

There should also be some air-direction doors down in the heater unit that move with the control. Maybe THAT's what is disconnected or broken.

 

Even with the key off, turning the temperature dial on the console moves the cable which moves the core valve.

 

OK, so it's not motorized. Sorry about that confusion.

But Honda's "traditional" way of doing things is for the cable to go down to some air-doors under the dashboard. Then from the doors, there's a 2nd cable going out to the water valve.

Look for the cable action under the dashboard. Seems like maybe the air-doors aren't moving the way they should. Then the heater core gets nice & hot, but the air isn't blowing through it.

 

I can feel the cable moving under the dash. So would the cable going out to the water valve move if the cable going to the air doors was not moving the doors?

Also, I stated that the engine was heating up properly, but I noticed today that the temperature gage does not go all the way to the halfway mark. Is that significant? It goes a little over halfway between cold and the middle mark.

 

Something below 1/2 is about normal. If the engine is indeed NOT getting up to proper temperature, then I'd say get a new thermostat. 25% on the gauge seems a bit low, but not so much that the heater wouldn't work.

One cable drives the doors, then the 2nd cable goes from there to the engine compartment to work the valve. Since the 2nd cable DOES work, then the question becomes whether the air doors can be broken in a way that allows the cable & external levers to work. I'd say you should FIRST check out your thermostat to see whether the engine actually heats up.

 

Jim,

OK, I found some instructions online for testing to see if the thermostat is working. Basically, it said to let the car run for a few minutes with the heater running, and then feel the hoses that go to and from the radiator. It said they should both be hot. I did this and the top hose was very hot while the bottom one had not heated up at all that I could tell.

Does that confirm that the thermostat is faulty? I thought if a thermostat was not functioning, that the engine would overheat. Is that not the case? Could you help me to understand the logic here? As you can tell, I'm not much of a mechanic.

Thanks
Richard

 

In response to your last post ^ you might have to let the engine idle just a little longer to let the T-stat open up.
If the T-stat was stuck closed you would see high temp on the gauge after 10-15 minutes of idle.
So far from the descprition and checking you've done it sounds like an air door malfunction, or heater core is plugged up.
To check for plugged up heater core..turn the heat control **** to hot let the car idle to operating temp, then check the 2 hoses at the fire wall for temp difference.