Car:91 Integra
motor: B18b1
Problem: No hot air.
Parts replaced: Thermostat,control valve (open/shut)
After trying a couple things, my heater is still blowing cold air.The last “guess” I have is that I used some “powder sealer” in my radiator last week, because of a hair line crack I had. Is there a chance that the “powder sealer” clogged something? I flushed everything,but still no HOT air. Anyone have this problem befor?
coulda been that stop leak or also make sure that the line from the heater valve isnt broken… and of course make sure that the car is warmed up to
Well the car ran for about 15min, just to make shure the colant got warmed up. As for the line from the valve being broken. Its in good shape. I’m starting to think that the heatercore got clogged up. If so has anyone on here taken theres apart?
those sealant things does more bad then good. they dont really clog up the lines but those little fins on things like heater core, condenser and radiator. check the temp on the block, radiator and hoses, then check the temp on the heater core. compare and you’ll find out if thats the problem. i think its a pain taking it out. a easier way is try to dissconnect the lines going in/out the core and blow it out if you got a compressor.
This sounds like a good idea.As for the lines. I let the car run for a few minutes and I felt the lines and 1 is hot 1 cold.
if theres a big difference in the lines going in and out while the car is warmed up and the heat is on. check to see if the heater valve moves when you turn the knob cool/hot air. if everything checks out good its probably clogged. imo i think its clogged cause those sealant stuff dont work that well. most cars that come in the shop i work in complaining they got no heat all of a sudden after the put that stuff on and useing some sort of flush chemical usually ends up clogging something.
Well I guess my only choise is to pull out the dash and get to the heatercore,and try to clean it out.
no point in taking it out and clean it. pretty much the same way you can clean it when its in there. just blow it out. or use a garden hose on it and blow it again. if that way dont work, then you take it out. i cant remember but i dont think its fun taking it out.
sure doesnt look fun… but yea… try shooting it out with compressed air and a garden hose
fill your radiator up with degreaser, remove your thermostat so it could flow without the car having to heat up and run the car in idle for an hour. i cleaned my radiator this way and it looks new inside again. oh and set the heat to high and turn on the ac to high too so the degreaser flows into the heater core. make sure you flush it out with water afterwards. This is a quote from another fourm. Has anyone ever tried this?
:wtf: i dont think i would ever do that, or never heard of that. this is the first time. i dont really know how strong is degreaser but thinking about “what if” the water pump goes or some seals. that would end up with more damage. besides if the heater core is clogged enough for the pressure of the coolant not being able to force it through. i dont think it will work. up to you to decide what to do.
true I was kind worried about trying something like that. Looks like I’m just going to try a air compressor first. If all else fails I’ll get a new core.
put a big piece of cardboard in front of your rad. See if you get warm air then. Did you make sure when you replaced the thermastadt that the “jiggler valve” was facing up towards the hood?
My heater didn’t work after this fix. Well one of my hoses to be axact the on that comes out the motor block and goes into the heater core al of the sudden appeared with a big ass crack. Well I changed it and i found out that the fix a leak thing clogged it up. Well the heater works like this, when you turn the dial to the hot position it opens a little opening. Well I didn’t really use the heater for a while, and I poured in the fix a leak thing. Then I end up without heater for a while. This shit happens and I find out that you know the heater dial is in the cold position which blocks the hot coolant from going to the heater core. Well like it’s clossed it stops all those little things that are in the fix a leak thing(look like little hairs). Well like I didn’t open it for a while they kept accumulating there. It clogged it up a lot so the pressure wasn’t enough to push it out when I wanted to use the heater.
Well to summarise this after I changed the hose I see all those things stuck in there I get my flat head screw driver and take em out and stuff. And bam after I finish putting the new hose, feeling the raiator with some coolant and letting my car warm up, my heater work again. I would get some pics, but I don’t got a DG cam. :crazy:
Hopefully it will help you out fixing the heater, cuz here in cali it’s getting colder everyday now.
As I changed the thermostat. I saw what look like little hairs. Kinda made me wonder how they got into my motor. I’m going to try replacing the lines and flushing the heatercore. It just been way to cold latley to do it.
U could just try taking off the line that goes into the the cabin. It comes out the motor block under the distributor and goes into the cabin, but first it connects to the little plastic that has the open close when u use the heater. try to take it off where it connects to that plastic switch and if the same thing happen as mine you will see that line is clogged up. Get a flat head screwdriver and take it all off. 
I’m having a similar problem but I atleast have heat when I’m moving. When my car idle or at a stop light, then I have no heat. Of course this all happen after I use Bar’s Stop leak. I flushed radiator and changed thermostat, but still doesn’t solve the problem. I think I will probably need to do a garden hose flush of the heater core.
Does anyone have any other suggestion?
im so ephing stoked right now, my car was having somewhat the same problem, and thank you ricoh for telling me the thing about the tube under the distributor, i found out that the person who had my car before me actually hooked it up to the return port under the throttle body, so thanks to him i found the actual return line hooked it up to the return port and connected the intake line into the proper spot… just gotta share my happiness!!! I GOT HEAT!!! FK YEAH MO FKA!!!
This sounds stupid, but I had the same problem.
I thought it was the thermostat, too. Replaced it, and nothing. So after a little bit of investigating, got to looking around inside. Turns out the little linkage that turns it from cold to hot slipped off.
What you do is, from the drivers side (just cause its easier), look up under the passenger side dash portion, behind the radio. Turns out peoples feet come close to the linkage when they are the passenger. Just check that.