I wanted to see if anyone here had any advice for me, I am a student and as I just moved here to Boston, so I don't have a lot of money to get my car fixed (who does). Also I just moved here from Arizona and it is snowing here, so obviously, I have quite a problem on my hands!

I have a 01 LS Blazer 2 Dr (non 4wd), 66000 miles. It has the manual (twist ****) heat. No matter how I turn it (hot or cold, A/C, vent, floor, defrost, etc), only cold air comes out, the blower works fine. The car drives normally, everything else functions fine and the temp guage reacts as you would expect (does not get too hot or overheat).

Recently had winshield replaced, recent full tune up etc, just before I noticed it went out. It seems the heat was working awesomely (very strong) last time I used it (although that was last Jan)

I was thinking some type of connection might have came undone? I checked all the fuses etc for the systems and everything is fine there.

I searched the forum for threads on this topic, and the only post that looked like it might apply to my problem is this one https://blazerforum.com/m_252/tm.htm

I don't know that I would be able to do this (flush core and hoses) myself as I don't have anywhere not outside on the street to work on the car. How much should I get charged for this if really thinks this is the problem.

Thank you all in advance for your help. I appreciate it.

 

I just read this great post (below)

I will go see how long it takes to get up to operating temp, and check the hoses to the heater core (I should be able to find them I think) and report back what I find (probably won't post results till later today/tomorrow)

 

First thing to do is make sure your overflow bottle is full of anti-freeze. If not, fill it to the full line with straight anti-freeze. bEing you went from a warm climate to a cold climate you will need more anti-freeze to protect to colder temps.

If you have a radiator cap, take it off and add striaght anti-freeze to fill it up.
Once that is done, drive the truck, safely for about 5-10 minutes with the heat on full blast.

Let cool and check to make sure both the radiator, and overflow bottle are still full. IF not, add more anti-freeze until they are both full.

I suspect your low on fluid and you have air trapped in teh system. Best way to flush the air is by what I outlined above.


If that doesn't fix your problem, post up. We can walk you through other things to check.

 

Hopefully you got my post before you left, it will tie in nicely with your second post.

By the way, welcome to the site. [sm=americanasmiley.gif]

 

Also, check the heater hoses. If they both are warm (one should be quite warm, borderline hot - the other not so much), then your problem lies with the mode door actuator in the dash. All of the door controls for the HVAC (heating/ventilation/air conditioning) are controlled by vacuum actuators.

A simple check to rule some things out would be to move your mode selector and verify that the air goes to the proper areas.
IE- When on defrost it blows out the vents below the windsheild, when on midlevel, it blows out the vents on the dash front, and when its on floor level, that it blows out the floor vents. You could go as far as to do bilevel and it should blow out the dash and floor vents. If any of them works, they all should work, but what that tells you is that your main vacuum line running into the HVAC system is connected and working. Side note... You must have the engine running to do this verification. If they don't work, then your problem is with the main vacuum line and is quite easy to fix.

If all of them work, then you may have to start pulling apart your dash to get to the vacuum lines inside. You can see some of them by dropping down the glove box. Open the glove box all the way. On the upper left corner, you'll feel a retaining hook. Push the glove box back in slightly and push the retaining hook out of the way, then pull the glovebox past. It should swing all the way to the floor. At this point, if you haven't already emptied your glovebox, gravity will have done the job for you. You can now see much of the HVAC housing.

I'll try to pull up some schematics of the vacuum line routing for you, but I can't do anything until later tonight.

Good luck. If you can get what I have said done before then I'll have a better picture of where to look for more information to help you out with your problem!

 

Ok, here's all of the information you should need:
#1 is the vacuum supply chart for basically all manual controls
[IMG]local://upfiles/667/0636AF64FCB54145AFED9E68DDED9328.gif[/IMG]
#2 is the vacuum supply chart for the auto climate controls
[IMG]local://upfiles/667/59B364FB2B1F473E848E4C7C20FDCBE3.gif[/IMG]
#3 is the vacuum line routings for all of the manual controls
[IMG]local://upfiles/667/87B2D0E3C13B466FB754888E733B61AE.gif[/IMG]
#4 is the vacuum line routings for all of the auto climate controls
[IMG]local://upfiles/667/2FA9C46AE8CD44CAB84990635C0B24F9.gif[/IMG]

 

Sorry to get back here so late. Had a little bit of a snowstorm friday (still got out to the car though) and have a final later today, so I was studying all weekend.

Turned on the car. Took normal time to warm up to operating temp (5-10 minutes). Turned on heat - nothing. All the vent configurations worked as normal though (ie, defogger through winshield, floor through floor, etc) Shut heat off it was making it colder. Popped the hood and checked the hoses. One seemed to be barely warmer than the other. I got back in the car for about 5 more minutes (it was snowing like crazy, but did not try to turn heat on during this stretch as it made it colder) Got back out and checked it again. Now the difference was more noticable. Got back in car again for 5 more minutes and checked one more time. Again even more noticable, temp difference between the two for sure.

So I assume it might be the blockage in the heater core swartlkk mentioned. Or was I supposed to have the heat on when checking the hoses?

Or perhaps is the air pocket Hanr3 also capable of causing this temp difference between the hoses? I did not read your response before I left, so I am not sure the coolant level. I can check it again in the next day or so. (The car is parked across town as there is no parking in my area in boston - long story)

Please let me know if you think it still might be a coolant bubble, or if it is for sure a blockage in the heater core at this point.

Thanks for the great posts guys!