Heater works intermittenly

tallt187 · 12-23-12, 02:02 PM

I have never posted on a forum before so please offer any advice if this posts in the wrong place.
I have a 1992 Acura Legend LS and the heater keep works then does not. When it does not work, it blows very, very slowly and the air is cold. It also makes a clicking noise. When is does work, it works great. Blows strong and the air gets plenty warm. I have never had a heater core go bad in any of my cars yet so just wondering if this is a sign of that. Hoping its just a fuse, sensor, or switch. The car has about 275xxx and runs awesome! I just did the radiator, all gaskets, all fluids, most hoses, timing belt, water pump, VSS, knock sensor, etc about 8k miles ago. Thanks!

L3GDKANG/JDMKANG · 12-23-12, 03:59 PM

Check pass floor board and see if it's wet. Then check your hoses that go to it under the hood.

BIGBOY · 12-25-12, 11:07 PM

First thing to do is bleed the cooling system. Trapped air causes inttermintent heat. They thermostat could also be sticking/stuck open (only use Honda thermostat.)

If your heater core was bad as mentioned you would be losing coolant and the passenger floor board/ carpet would be wet.

tallt187 · 12-27-12, 07:21 PM

Thanks for the responses. I always use genuine Honda for seals, sensors, t stat, gaskets, and fluids. The passenger floor board is completely dry. This is actually my little sisters car so sorry for delay in responding. I did notice that the outer vents will blow a little air but nothing in the center vent or defrost vent. I can hear the fan selector switching from defrost to vent to floor etc but very little or no air at all coming out. Does not work on AC or heat. I checked the box under the hood and nothing labeled heater fuse or relay. Any idea if this car had a fuse or relay for the heater fan? I asked my sister to bring the Chilton manual I bought her but of course she forgot it at home! Thanks!

I just checked all the fuses in the kick panel and they all test good as well. I see there are some relays attached to the top of the radiator and the lid does not have a guide for what they are. Any idea what relays are in there?

BIGBOY · 12-27-12, 10:53 PM

It sounds like the blower motor has failed to me. What I would do is apply 12v directly to the motor, if it doesn't spin that is the problem.

tallt187 · 01-01-13, 02:20 AM

Motor fan was the culprit. I hooked it to the battery and nothing. I ran down to my local pick n pull and only two compatible cars. First one had already been taken but the second one still had it. Once I got it out it had a date on the motor of 2007 so it had been recently replaced and should be good to go for many years. Not bad for 15.99! Thanks again for all the help. I was also able to find step by step instructions in the DIY. Removal and installation only took an hour at most.