Heater core?

need manual CHECK IT @ https://www.2carpros.com/kpages/auto_repair_manuals.htm _________________

Blower motor works, but I am not getting any heat. Heater core is not leaking and no smell. Temperature is reading good.

Once the engine warms up and the thermostat opens up feel both heater hoses going into the firewall, under the hood. The should now both be hot. If one is hot and the other cool or just warm then the heater core is clogged. If so, you could try back-flushing but if that does not knock loose the clog, then you will have to replace the heater core.
If both heater hoses are cool or just warm, see if there is a heater control valve located on either of those heater hoses, then if so, check the hose in front of and just after that valve and make sure they are both hot. If now, see if that valve vacuum hose fell off, etc., or if the valve is just stuck.

Here is a guide that can help as well.

https://www.2carpros.com/articles/car-heater-not-working

Please let us know what happens.

Cheers, Ken

What do I have do to access and replace yhe heater core on this vehichle. :x

The throwout bearing is what pushes against the fingers on the pressure plate and disengages the clutch to allow the shifting of the tranny. The bearing is failing but it still is doing its job. However, it is starting to grumble like an old man and replacement of the throwout is part of a clutch replacement. Replacing the clutch is very near for you.

Bruce Hunt is right.
you could have a clutch problems or internal transmission problems : neutral rollover rattle,damage input gear bearings misalignement of transmission with engine, worn or damage bearings . check your fluid level first, it could be low.you could also have worn or brokken gears , excessive counter shaft end-play, or the main shaft gears are loose.

Well , patients , but the underside of the right dash below the glove box has to come off and the heater core removed from the inside , make sure to block hoses off before repair,
JIM

In your answer you mention the underside of the dash on the right side needs to come out. The shop manual says you have to pull the whole dash. I'm hoping that your alternate route is what it sounds like. I'd appreciate your advice.

By the way, my vehicle is a 2001 S10 4DR, 4WD Blazer and the heater core is leaking too.

Thanks for your time.
Jerry

when I drive with the heater on it's only putting a small amount of wram air out if I have the RPM's up it;s warmer but when I idle it starts blowing out cold air how do I replace the heater core?

o1 is a little different , the whole dash does not have to come out per say , remove heater hoses and block off , remove speaker covers and center defroster grill you will find a bunch of phillips head screws along the op remove all but two , remove all lower dash covers , and there are six main bolts that do not have to come out but losse , if you look hard you will see which ones would make the dash fall toward the seat , then remove two top scews you left in , dash will fall back and you have a few more screws on the core cover , book calls for 1o hrs ive done them in six but i break it up into two days so your not stuck under there all day

you might try a good radiator flush and then taking a hose and back flushing the heater core before going the trouble of replacing the core, especially if it's not leaking. You have to pull the dash out to get he heater core out on that model.... Of course check to make sure that you have afull coolant as that will effect your heat if it is low. If itis then have your engine pressure checked as you may have a bad intake or head gasket.

As you can see by the pictures I got the dash to lean out and I took out all the screws of the A/C module box but it's not coming apart. If I lift up on the top of the case it gaps open but it appears it's still connected together. To go further It looks like the dash is actually going to have to come out. This appears to require letting the steering column down, unplugging several major electrical connections and getting into the Air Bag controls. That's really my biggest concern, after all this I'd hate to fire off the air bags and add that to the job. Any help is appreciated! Thank you, Jerry

go under the hood ontop of the evap core , and there sits the blower motor resistor , there are three bolts , you will not be able to see them but there is a cutting guide on the housing to cut the plastic to reveal the bolts 5.5mm once the resister is pulled look down into the box and you will see one 10mm bolt that needs to come out , also there are two under , one is behind the right exhasut manifold and the other is same height but closer to the right wheel , these two go to studs on the lower right corner of the ac module and one right next to the heater hoses and its out , sorry about that i thought you meant just the dash , warning the one behind rhe exhaust manifold is tricky 10mm one turn at a time , and if you do want more room you can drop the column should be 4 retainers 10mm and two column boilts 15 mm but i alway snuck em out without it , its tougher but savers about 20 minutes in the round trip, oh and i never unplug anything i always more a harness from a clip if needed , no sense in pulling what you dont need, as long as the battery is disconnected the air bags will be ok , remember all you need to do is to pull the module out enough to clear the heat core lines on the inside of the firewall to remove the two top cover bolts , thats why i never go too far

I was able to locate and remove all the fasteners you told me about and I even found one extra. However, the whole box wiggles but isn't coming away from the firewall. Does it have anything to do with air distribution vents on the bottom of the box for heating? They seem to be separate but I'm wondering if they're in the way. I'm so close to getting the core out and this one last thing is holding up the show. I haven't given up though.
Thanks for your time.
Jerry

My SUV does not get heat. air conditioner works fine, replaced radiator, heater core, thermostat, purged all air out, actuator seems to work, it just does not get heat.

as long as you have the tree plus the one one the firewall at the heater core lines you should be good , the two on the lower firewall are studsthey may be holding you up and as long as you pulled theresistor out and got that one give it a yank

With the engine at full operating temperature, locate the two heater hoses where they go into the firewall and feel them to see if they are both hot to the touch. If they are both hot, the heat in that vehicle is controlled by a blend door that regulates heated air flow. it is operated by an electric motor/actuator. The problem can be that the actuator is stripped or inoperative or the door itself could be damaged. This is what needs to be determined by examining the actuator and see if it is responding to heat change commands or not.

Indeed there were the fasteners you told me about but there was one more WELL HIDDEN lag bolt looking thing that went in from the firewall and fastened the outside Evap cover going all the way through into the A/C box. It took me an hour to find it but it's right by the passenger side valve cover on the fire wall. It took a 24" 3/8 drive extension and a 10mm universal socket to get to it and that was pretty tight. Once I took it out the whole box popped right out and I'm about to remove that *^&%&*@## heater core. Now if I can just remember how it all goes back to gether. :mrgreen:

Many thanks for all your help. I'd still be pulling my hair out trying to figure this out without it.
Jerry

hey no problem, , its always easier going back in ,

jim

Went down to my local O'Reilly Zone and got a heater core. Looked OK until I dropped it in and it wouldn't seat? Took it back out, checked it over and tried again. STILL wouldn't work. Looked closer and noticed aftermarket core, bottom tank is square. The one on the OEM is half-round. Groan... Paid a visit to my local Chevy dealer and sure enough, they have the right one for just a little over double of the aftermarket price. Well, what are you going to do? Got it, took it home and I'm well on my way to get this thing sewed up and back on the road.
I cringe to think what this job would have cost to have someone else do it.
As I said before, Many Thanks!
Jerry

no problem , i worked at the dealer for 20 years and the parts always work best , next time , order ahead from gmpartsdirect.com , almost half of what the dealer charges and it would have cost you about a grand or so depending on what part of the country you live in , im glad i could help guide you
jim

I NEED TO REPLACE MY LEAKING HEATER CORE. WHAT IS THE PROCESS? CAN I DO IT MYSELF?

if you know what your doing a repair manual would help you out allot. if not i would suggest having a professional perform the task

Six cylinder four wheel drive automatic.

I need to remove my dash so I can replace my heater core. How do I remove the dash? I know where the heater core is located, do I need to remove the entire dash, or just the dash panels where the heater core is?

The entire dash needs to come out. It is not a fun thing to do. You should have a copy of the manual to do it easily. In short you need to disconnect the battery, unbolt the steering column from the dash. There are a bunch of bolts that hold the dash in. one on each end under the dash, two or so in the middle under the dash, then there are bolts hidden behind the A/C vents behind the speaker grills and behind the defrost vent. Once they are all out the dash can be moved out of the way enough to get to the heater case. Figure about six hours if you have done it once longer if you need to learn as you go.

How to replace the heater core in a 1997 Chevrolet Blazer?

how do i install the heater core on a 1997 chevy blazer s10 4 wd 4.3 engine

if it's got a/c you have to have the charge recycled then you have to pull the dash and finally the heater core.

1997 Chevy blazer 4.3 160000 miles will the oil pressure switch cause a no start condition if it fails and what checks could be done on this problem.

Okay. car ran fine before replacing heater core now a no start condition.put dash back together hook battery. back up.Now thecheck engine ligt abs batt andairbag is on no tart codition engine turns over but wont start.i have checked fuses and relays seem to be working i now dont here the fuel pump kicking on when i turn the ign. on.I AM in the process of going through ignition sytem.i have replaced the switch harness under the steering column.any input or advice to point me in the right direction would be great thanks

It can only cause a "no start" if the fuel pump feed is shorted out. All you have to do is unplug it to eliminate that possibility.

All "crank, no start" conditions are approached in the same way. Every engine requires certain functions to be able to run. Some of these functions rely on specific components to work and some components are part of more than one function so it is important to see the whole picture to be able to conclude anything about what may have failed. Also, these functions can ONLY be tested during the failure. Any other time and they will simply test good because the problem isn't present at the moment.
If you approach this in any other way, you are merely guessing and that only serves to replace unnecessary parts and wastes money.



Every engine requires spark, fuel and compression to run. That's what we have to look for.

These are the basics that need to be tested and will give us the info required to isolate a cause.

1) Test for spark at the plug end of the wire using a spark tester. If none found, check for power supply on the + terminal of the coil with the key on.


2) Test for injector pulse using a small bulb called a noid light. If none found, check for power supply at one side of the injector with the key on.


3) Use a fuel pressure gauge to test for correct fuel pressure, also noticing if the pressure holds when key is shut off.

4) If all of these things check good, then you would need to do a complete compression test.

Once you have determined which of these functions has dropped out,
you will know which system is having the problem.

i did a fuel pump test it did not hold when i turned the key off so i will try unplugging the oil pressure switch and see what happens thanks so far. but it almost sounds like a bad ground dont no how t o check that

It's neither of those. It's not electrical in nature at all. You have a leakdown problem. This can happen at a leaky injector, pressure regulator or bad check valve in the pump.

What is the fuel pressure at peak?

it was 60psi and this will cause all the warning lights to light up on the dash? ok i will do the checks. it sounds like it might be more than one thing.will check back after the ign. testing side of it .thanks, it just makes me feel silly it ran fine before the heater core replacement and now nothing works didnt expect that,will keep u posted thanks again

No, the fuel pressure is an issue but not preventing it from starting. As long as you can keep it up around 60PSI when cranking, it will run. Make sure that pressure that you are losing isn't an internal leak fouling the plugs. The dash lights have nothing to do with that but being on when the engine isn't running isn't unusual.

kool thanks will keep u posted

Heater problem
1997 Chevy Blazer 6 cyl Four Wheel Drive Automatic

do you have to take the dash off to get the heater core in, if so how do you get the dash off?

Yes, the dash has to come out to R&R the heater core. It is NOT a fun job and you really should have a copy of a manual for reference if you have never done it before. There are quite a few bolts and clips that you need to remove and some are in hidden places. The Mitchell online manual covers it real well and isn't expensive.