Check out our top sponsors:

  • Bitcoin Affiliate Program. Earn 5% to 70% commissions
  • Post Your Business Here
  • Complete list of sponsors

Search this Forum:

Auto Finance Made Easy! Get Approved Today.

Used Cars for sale - Used Trucks for sale [3120341940] Buy Used Cars

no heat

- Chevrolet-Blazer

Forum Post
09/14/08 11:29
Luke Warmwater

no heat

97 S10 Blazer no heat

I get barely any heat out of my blazer, the engine temp and thermostat are ok.

There appears to be no circulation through the heater core - only one hose is warm.

The temp selector potentiometer seems to there a a/c control valve in the heater core water line?


Archived Replies

This post has a total of 53 replies. The most recent 25 are shown below, you can view the complete archive here: no heat archive. Your feedback, comments, opinions and questions are welcome and encouraged.

This forum post has messages dated from 09/14/08 through 05/19/11, please be sure to read all the messages. If you feel it is old or outdated, please follow up with a question or comment and someone may be able to update it, or reply with newer information if you have it.

**/**/** **:**

I have a 2000 Blazer and a few weeks ago I was getting a terrible smell and my window were fogging up. I just spent the last two days replacing my heater core, which was definitely the problem (the old heater core was leaking badly).

Now I am still not getting adequate heat and the windows still fog up, although not quite as bad as before. The engine takes a while to warm up, giving me luke warm heat inside the cabin. Then, the heat goes ice cold, and the engine temp spikes to 230 degrees.

I checked the hoses going into the (new)heater core, and one seems to be a bit cooler than the other.

I am thinking of doing a coolant flush, then changing my thermostat. Any comments or suggestions would be great.

**/**/** **:**

can some one show me a picture a electronic heater control vaive that control the flow to the heater core.
**/**/** **:**

My 200 Blazer S10 blows luke warm air. I've read some good ideas, like blowing out the heater core.

Can anyone tell me more of the switches or controls under the hood? My dash contols seem to be doing their job.

**/**/** **:**

i have 97 blazer and it overheated yesterday heat and air was working just fine until then. now the heat and air will work on the dash and floor but nothing comes out of vents.....then today the service engine soon light came on can anyone tell me whathe problem is
**/**/** **:**

i have similar problem on my chevy blazer vehicle. it has no heat and checked some parts and the potentiometer is fine. took it to the mechanic.
**/**/** **:**

Have 99 Blazer. No heat coming thru and truck overheats in 10 minutes. Checked fluid levels, replaced thermostat, and still nothing. Touched top hose was cold. Does this mean the water pump is shot and no coolant is getting thru the engine? there is no heat either in the truck. HELP!!!
**/**/** **:**
Charles Coverdale

I have a 97 Chev. Blazer S-10. When you first start it in the morning, with the heater off, no heat comes out. After you restart later with the heater still off, max heat comes out. This will occur all day until the next morning start up. Any suggestions?
**/**/** **:**

Some of you guys even removed the dash board, and everybody overlooks the top and bottom radiator hoses, specialy the suction hose wich is the bottom radiator hose and if it is the

original hose most likely is getting soft as soon the coolant gets around 180'and collapses shut even with the spring inside

reploace it with a good after market hose with heavy duty or

double anti collapse spring and kiss your problems away.Water

pumps problems are:loose belt if it is a vee belt or leaks at

the shaft seal, one in a million a broken impeller but you will know because the noise, so guys check those hoses.

**/**/** **:**
Steve Martin

I have a 1996 Chevy Blazer and the heater switch dont work on the high position, I have replaced the dash roll switch for the fan with a new one and I replaced the other electronic switch under the hood for fan speeds. Do you have any ideas?
**/**/** **:**

My 2000 blazer was not getting any heat in the cab. I checked the hoses. One hot one cold. So I took them both off blasted the core out with a power washer. What appeared to come out was the same type of calcium we get on our plumbing fixtures in our house. I used the house water to mix with my coolant previously..could this be why the filter in the heater core keeps clogging yearly? Would it benefit me to flush the coolant and use bottled or purified water to mix with the coolant? And also blasting this out makes the heater blow as hot as a new car which is awesome since I was quoted about 400 by a shop to fix the heat.
**/**/** **:**

I flushed my heater core on my 2000 Blazer both forward and back. I had a large amount dark brown water come out in both directions and continued to flush it out until nothing but clear water came out. I disconnected the hoses from the block and flushed through them to get both of them cleaned as well. After a small topoff of antifreeze and a short drive the heater works GREAT! Tomorrow the other Blazer gets it as well as the truck whether they need it or not. It was well worth the try.
**/**/** **:**

I chane the heating core for my blazer 96 and still not getting no heat or ac out what can it be
**/**/** **:**

I have an 1989 chevy full size blazer when i turn on the heater it barely warms up even after driving miles. the thermostat has been replaced with diffent tempertures. the heater core is fine both hoses heat up but no hot air. can someone tell me why
**/**/** **:**
Ryan D.

I have a 99 blazer. My heat resently went out but before the heat went out completely it was just blowing out warm air; now only cold air comes out.

I dont smell antifreeze so i dont think its the heater core. I also put in coolant so its not that either. Some people have told me it could be either the thermostat or the heater control valve.

Any ideas anyone?



**/**/** **:**

2000 chevy blazer low heat water muddy new thermastat what to do
**/**/** **:**

I put in a 195 thermastat and it goes up then comes back down to 160 some times gm put in oversize radiators so that the engines would run cooler in warmer weather the desert for instance. if you see antifreeze on the bottom hose or in that general area it is probably the back bearing of the pump and the antifreeze is coming out of a little hole on the bottom of the waterpumpshaft. and sometimes you have to bleed the air out of heater core to get heat all you have to do is take the radiator cap of let it warm up and and open the bleeder if you have one if not you might want to put one on the return line of the heater hose. and in some cases you have to block off some of the radiator in front with something like cardboard to get heat to slow down the cooling process. if you have a two core radaitor it, the people who designed them designed them to be actually a three core so they wiil cool the fluid twice as fast. but most of the time when you smell antifreeze inside the vehicle it usually meens you have a small leak in the heater core. remember all you need is a auto repair manual from your local library chiltons has more demographics in them.
**/**/** **:**

my temp gauge on the dash bored is not getting about 120, and heat does not work. the fan is on all the time. if i remember right the fan has i clutch, but i could be wrong. there is not flow in the radiator. i do not think it is the heat coil. please help i have to drive back home 724 miles!!!!!!!!
**/**/** **:**

i have a 01 s10 blazer wow my heat while standing still at 195

blows excelent heat but when i take it for a drive it cools down to luke warm almost cool i have replaced the heater core the radiator the hoses the water pump the modulator valves and recalibrated the blend door now i have no clue where else to check yes its the right heater core and no the head gaskets are fine have very hot heater hoses this started after haveing it to the dealer for wireing repair after the remote start went bad cant find anything unplugged or disconnected i need help i cant afford to take it in any more and i live in minnesnota its cold here

**/**/** **:**

I wish chevrolet had this money pit Blazers shoved where the sun don, t shine.what was this some kinda experimental crap car. I can, t think of anything on it that hasn, t felled including the heater. Two transmitions , door windows front end and wheel bearings and abs sensors.Brakes It ain't no wonder they roll over on people. I bought a Ford mustang and trashed that piece of crap . And unless you have a mac daddy wallet you better do the same
**/**/** **:**

I have a 2002 blazer. The heater works fine while driving. When at idle it starts to blow cool air. Any suggestions?
**/**/** **:**

(Using a garden hose to pump fluid into the system to get air out will just fill the system with water and not coolant.)

Cold air due to;

1)Air in system, it won't come out like you would normally do on a small block chevy. You have to get basically get it professionally done. (winter time definitely)

2)Thermostat is done. Change that and you'll have to do #1 anyways.

3)Water pump failure. No water movement = no heat in vehicle but a nice plume of white smoke in engine.

4)Heater core filled with gunk. Dump a little coolant out, and run some Prestone rad flush for while, dump old coolant and replace with new stuff. You will get air in the system doing this so get the air out with #1.

5)Heater core done son. if you smell coolant in the vehicle/windows fog up and you didn't just over heat it, or dump some on the carpet from extra coolant you keep in the car, you need a new heater core.

Those are the major reasons. If you decide to blow air through your heater core, and you pressurize with a compressor like I did on my FireChicken, you will definitely need a new heater core as the copper tubes are thin and weak like little girl. Oh and the orange crap chevy puts in their rads tends to leave a residue that looks like rust allll in the cooling system so flush that pos regularly.

**/**/** **:**


Your heater core is blocked. I have the same problem

1) Loosen Radiator cap,

2) Remove both hoses from the core. The one on the left when facing the fire wall from the radiator is the supply

3) Get a piece of 5/8" Heater hose and put it on the return

4) Put a can under the supply line (This is 3/4" Heater hose I think)

5) Blow back on the piece of 5/8" Heater hose so you reverse the flow through the heater core

6) Catch all the crap in the can. It does not take much to block the core

7) Reconnect all the lines and add coolant to the radiator if it needs it

YOu can do this whole process in about 10 minutes

I use a piar of channel lock pliers to get the clamps off at the heater core

Hope this helps

**/**/** **:**

I have a '99 Chev. Blazer s10. No heat. Blower is good. Changed leaking water pump, new top and bottom hoses. Also new thermostat. Fluid was clean pink like new before I started. Still NO HEAT. AC PUMP KEEPS starting and stopping. What is that all about??? Besides this nightmare it's a pig(I mean SOW) on gas. Maybe the people that designed this monster should be in jail! It's clear to me that we all have been screwed by GM. I've been a GM customer all my life and considering a Ford (they didn't need bailout-extortion money from the government). If anyone can help me please reply. Thanx. JB
**/**/** **:**

I have herd a wise tale that the stock coolant in these particular vehicles will gum up over time, being the new owner of my little brothers truck that my mother gave to him ( that im really not proud to be working on because he gave it to me)


2 years ago the dealership told us it was a sensor,

we replaced the sensor to re-activate the heat,

that worked for about half a year then it just blew cold no matter what temp you set it on (btw that charged us about 750 bucks)

I decided to take a in depth look: i flushed the complete system,

and fond some thick brown murky content in the coolant system, (I about freaked out cause I thought I had a cracked head)

Turns out that isn't the case, My 98 Chevy Blazer uses a proprietary type of coolant and as it ages it tends to gum up,

so I flushed my coolant system but that didn't work so now I am thinking of replacing sensors that may have that funky sludge built up on the sensors, , I really do think it is something electrical prohibiting me to have heat in the cab.

The reason why I think this is because: My engine does not overheat, I do not have water in my oil, and I do not have white smoke comming out the tail pipe. Also this truck has been on the road for 1.5 years with the same issue and the motor has not seized

**/**/** **:**

The most popular car in our country is Cruze model.. apart from the other brand of chevrolet.. the model is new and different..

Reply options
Share your opinions, advice, questions or comments on this post.
Be Heard: Forum reply options:

We encourage everyone to share their opinions, comments, thoughts and information, please consider sharing...

We would like to thanks all those who have participated in our community. All the great information available on our sites is because a member of our community took the time to share it. Thank you!

  • Reply to this Forum post (opens small window)
  • Social Networking

    Share this with your friends on facebook, twitter and Google+

    Social sharing because it feels good

    Please share this page on your favorite social networks:

    Please like our facebook page for Cars for Sale:

    Archived Replies

    This post has a total of 53 replies. The most recent 25 were shown above, you can view the complete archive here: no heat archive. Your feedback, comments, opinions and questions are welcome and encouraged.

    Chevrolet Forum Topics

    Chevrolet 1500 Pickup ForumChevrolet 2500 Pickup ForumChevrolet 3500 Pickup ForumChevrolet APV ForumChevrolet Astro ForumChevrolet Avalanche ForumChevrolet Beretta ForumChevrolet Blazer ForumChevrolet Camaro ForumChevrolet Caprice ForumChevrolet Caprice Classic ForumChevrolet Cavalier ForumChevrolet Celebrity ForumChevrolet Chevette ForumChevrolet Citation II ForumChevrolet Corsica ForumChevrolet Corvette ForumChevrolet El Camino ForumChevrolet Express Van ForumChevrolet G Series Van ForumChevrolet Impala SS ForumChevrolet Lumina ForumChevrolet Lumina APV ForumChevrolet Malibu ForumChevrolet Metro ForumChevrolet Monte Carlo ForumChevrolet Nova ForumChevrolet Other ForumChevrolet Pickup ForumChevrolet Prizm ForumChevrolet S10 Blazer ForumChevrolet S10 Pickup ForumChevrolet Silverado 1500 Pickup ForumChevrolet Silverado 2500 Pickup ForumChevrolet Silverado 3500 Pickup ForumChevrolet Spectrum ForumChevrolet Sportvan ForumChevrolet Sprint ForumChevrolet Suburban ForumChevrolet Tahoe ForumChevrolet Tracker ForumChevrolet TrailBlazer ForumChevrolet Venture Forum
    Top Searches: • chevy blazer heater problems • 2000 chevy blazer no heat • 2000 blazer no heat • chevy blazer no heat • 2000 blazer heater problems • 2000 chevy blazer heater problems • blazer no heat • chevy blazer heating problems • chevy blazer heater not working • 99 blazer no heat • no heat in chevy blazer • 2001 chevy blazer no heat • 1999 chevy blazer heater problems • blazer heater not working • 1999 chevy blazer no heat • 99 chevy blazer no heat • 2001 blazer no heat • 98 blazer heater problems • 98 blazer no heat • 96 blazer no heat • 97 blazer no heat • 2001 chevy blazer heater control valve • 2001 chevy blazer heater not working • 1999 blazer no heat • 2001 chevy blazer heater problems • 98 chevy blazer no heat • no heat in 2000 chevy blazer • chevy blazer heat not working • 2000 blazer heater not working • no heat chevy blazer • no heat in blazer • 1997 blazer no heat •

    Important information.

    This page is part of a social network. People may choose to participate here for personal, commercial or other reasons. Please keep in mind that posts or other information here may be: 1) advertisements and not personal opinions, and 2) that any products or services mentioned here may not work exactly as the promoter describes or promises.

    Please verify all claims and use an escrow service for any signficiant purchases.

    Used Cars for Sale. Sell your car. Buy a used car. Buy a new car. Buy a car. Sell a car. Autos for sale. Want Ads. Car Parts. Automotive Accessories.
    All ads on Classifieds1000 are the responsiblity of the posters; keep in mind, anyone can post anything!

    Copyright (c) 2005-2014 GLR Sales LLC.


    Privacy PolicyDMCA PolicyWrite for us • -- WelcomeSitemap
    Chevrolet Blazer 'no heat'