Okay, just signed up on the forum. Was refereed over here from a fellow member, not sure what his site name is here, but I'm from jbody.org.

Now, before i get the please search, know, that I did. While the problem i'm experiencing is common, the particulars are different for me. It may be the same fix, but I wanted to make sure I asked before throwing parts around.

Now, what I'm having a problem with is having heat and not having heat. It seems that when the temperature is above freezing, we have some heat. It's not GREAT, but it's something. When it drops below freezing, we have "cool" air. I've flushed the heater core twice. The hoses going to the heater core are NOT both hot. One will be hot, the other will be just warm, I can grab it and hang onto it for a good while. After flushing the heater core with the garden hose, the hoses will both be hot, but by the end of the day, I can grab the one hose again and we have no heat, again.

Now, I have cold air, I have warm air, and I have the temps in-between, but no hot air. It's getting cold here and I'm tired of freezing my nuts off.

So, now, because I have both cold, and warmish air, I don't believe it is the bleed door actuator, but I may be wrong. it could be the vacuum ball, but again, the temp does change, but not as much as it should.

I'm thinking it's something in the heater core, or the HVAC controls, but I'm not sure.

Help would great.

 

how does your rad fluid look? sounds like it's getting clogged really fast haha. mine did the same thing, I flushed the system and it didn't really help. flushing the heater core separately made the heat work great. I guess my core was so plugged up that the rad flush stuff I used didn't make it to the heater core.

your coolant is full, correct? a little bit of air in the system will cause you to loose heat intermittently

how well does water flow through your heater core when your flushing it?

 

do check the coolant level as I had one in today down on coolant and that was the no heat problem. Coolant loss I believe due to bad clutch fan but in your case check where the coolant hose attaches to the intake-it is a smallish nipple that sometimes gets plugged-even partially, causing, on occasion your issue. Easy to check. Jerry

 

The coolant looks okay, even though its new, it's still not great. It's a bit cloudy with dirt, but it's not oil. It's not a milky color, it's cloudy, like dirt deposits. Now when I say I flushed the heater core, I flushed just the heater core, and it flows quite well. Not a problem with flow, but the coolant that comes out is pretty gross, each time.
I will check the where the hose attaches to the intake. I'll bet with how gross the coolant is it's probably pretty plugged.

Where the best play to burp the system? Just leave the rad cap off? Thats what I've been doing, just want to see if there's a better place.

And yes, the coolant is full and new.

Oh and since I have so much dirt in the coolant, what's gonna be the best way to flush the whole system? I think I'm going to have to flush everything at the same time to get all of this crap out. I want to get it done with and not have to flush this thing over and over.

Thanks for the help, I'll take a look at the hose on the intake.

 

How can the coolant be new and the color you describe? Anyhow...you need it CLEAN before we go too much further. I'm sure that there is a thread on this site telling you exactly how to do it as I have to go to work now. Check in later. Good luck. Jerry

 

my old blazer did this to me all the time. somehow got air into the system from time to time. i used to put the front up on a snowbank or big curb to make sure the cap is the highest point and eventually the air would make it out. might sound dumb but are you flushing the heater core both directions? that cloudiness you talk about i would think has the problem. there are plenty of threads on here talking about dexcool read up on it, it should explain whats happening.

 

easy, drain the coolant put new stuff in, all the buildup/crud/etc the dexcool left behind is now in the new coolant. Why a flush is important... just beware if your coolant is THAT bad you have the possibility of flushing out crap that is 'plugging' a leak...

 

Understood.

Going to flush it running to try and move this **** out.