clm

My '88 Accord LXi has very, very poor heat. Last winter it would take 25 minutes to almost get lukewarm and it wouldn't get any warmer than that. I have a feeling it's the heater core, but I'd like more input before I remove the dash.

Currently, the car does not overheat and the temperature gauge stays just below the middle point, the A/C works, the hot water valve moves with the temperature control switch, all the blower speeds and vent switching work with plenty of air coming out, the rear defrost works, and I've bleed the system of air. The radiator was replaced a couple years ago, a few coolant lines over the past 6 months, the thermostat about 6 months ago, and I haven't noticed any interior or exterior coolant leaks. The upper radiator hose is hot and the lower radiator hose is very warm, so I don't belive the thermostat is an issue. The radiator fan also works if that makes a difference. I checked the heater hoses a couple days ago and IIRC the inlet hose was warm and the outlet was cold/cool, so I tried flushing the heater core with a garden hose thinking there was an obstruction. Flushing the core didn't appear to help, but I saw more mineral build-up in the heater hoses and a little bit of crap come from the heater outlet hose.

Any suggestions other than the heater core? I'm going to take another look at in the morning and to double check that there isn't any coolant on the floor. I might even try flushing it again even though it was a mess the last time.

Thanks for any help.

YeuEmMaiMai

simple test.

start car and let it sit and warm up. does it blow hot? if it does, put car in gear and drive around. Does the heat get cold? if so, replace thermostat....

clm

It never blows hot - idleing or driving. Like I said, it'll get close to lukewarm after about 25 minutes of driving.

clm

I took another look at everything today and it's blowing warm air, but not hot. All the cables are working, but the the number 1 blower setting doesn't work and air doesn't blow with much force out of the vents. The inlet hoses for the heater core are hot and the outlet is warm.

So at this point I don't know if it's a heater core, blower motor, or duct issue. So any suggestions or experience before I dig through the ducting and blower motor?

YeuEmMaiMai

ok you need to see if the door for the outside air is working properly.... does the control unit proeprly change your settings (IE from floor to defrost)?

clm

All the different air direction settings work as far as the linkage moving goes. There could still be some sort of obstruction preventing full air movement, but the different settings do move some air. I believe the recirculation valve works, although, I didn't check it since I always keep it on recirculate cabin air to avoid bringing fumes in (it's the beater!).

Thanks for the help.

clm

Bump.

hondadude

air flow? maybe the fan is full of junk or the evap fins are plugged up?
It's not too tough to hook up a garden hose to the heater core lines and flush that sucker, or at least see if there is good flow. Don't try unhooking from the fire wall connectors though, that thin metal will bend easily.