well here is my problem i have an 87 trans am gta with the 350 tpi and the heat doesnt really work but ac works fine except for the vents dont blown right well atleast not out the right ones now the heat only blows warm when the temp gets close to 220 and if its set on the lowest speed on the switch and idk what to check first to see what could be causing this and the when it blows it blows out the top towards the winshield till i start drivin then blows out the vents in the front and same for the ac so anyone have any suggestions or ideas anything would be great thanks
-Eldin

 

have you checked your coolant? low coolant would cause your heater to stop blowing warm air.

 

How about some punctuation to make your question easier to read!!!!!!

Check the valve above the front right valve cover, make sure it works properly. @ $25 to replace.

Heater core my be clogged. @ $30 to replace.

The problem with the air going to the correct outlet, defroster/vent/floor is a vacume issue. I took my HVAC control panel out, then took it all apart, cleaned it up real good. Solved my issues with the air control.

(I broke a plastic vacume line under the hood when I replaced my heater core too, so you may want to check them.)

 

ya might as well get a rad flush done too.

 

Does you fan actually blow good? Or BARELY?

 

Nowhere in his post does he indicate a problem with the fan itself.

This seems to be just an old heating system that needs some attention. I would do the following

1. Remove the HVAC controls, make sure the rotating disc that controls the vacume routing operates correctly.
2. Check radiator - replace if needed, don't forget the hoses, and flush the system
3. Diverter valve - Check to make sure its operating correctly, replace if needed
4. Heater core - most likely it is in need of replacement, if it's not fully clogged, most likey it's partially clogged. During replacement, I broke a plastic vacume line, caused the air to blow just out of the defroster vents.

My car was very similar when I got it. I had to replace the radiator soon after I got it because it was cracked. When i got my car, the air would come out the vents or floors sometimes, but it always ended up coming out the defrosters. So I fiddled with the HVAC controls, cleaned them up. Still just blowing luke warm air on the low fan setting though, but at least it was blowing were I wanted it to blow. I then replace the diverter valve because someone told me that was the problem, but it wasn't, still just blew luke warm air. So I finally bit the bullet and replaced the heater core, all is good now.

 

How nice of you to point that out...Like I can't even read. Thank you SO VERY MUCH.

He also doesn't indicate that it DOES or DOESN'T.

No air blowing would also feel like no heat.

Excuse me for looking fora possible simple solution, before diving into the hard stuff. It really sucks to do big "repairs", only to find out it was a simple problem.

 

Well, he also states that the AC works fine. Which if the fan was bad, I highly doubt that he would state that, especially if the fan wasn't blowing proper speeds. I'm sure he would have mentioned that the fan was only "barely" blowing.

And I am steering him in the possible direction to a fix, as a bad fan would not cause any of the issues he has. So your sending him in the wrong direction.

Non of these are repairs are "hard stuff" anyways.

So calm down a bit, I'm just trying to help this guy out.

 

especially when it comes to the heater core, not exactly a huge job but im a pretty big dude and it took me god knows how long to swap my heater core. just a weird spot to get at without pulling the entire dash. made up some cool new words tho

 

As was I......VERY common here on TGO, to not fully explain their problem or leave some point out.
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I've done 3 heater cores before, so I know what it takes

And you know? I PAID to have the last one done! Yes, it cost me $, but no headache afterwards or busted knuckles from reaching up in there.

 

if its gotta be done again the cars goin for her first trip to a garage other then my own

 

There could also be a rodent clogging up the air flow, why didn't you mention that? After all, it is a possibility too, even though he didn't describe a foul smell. We could go on all night like this, but it's a waste of time. Like having him check out his fan motor. What it comes down to, is a bad fan would not help out any of the others issues. That's why I ruled the fan out as a possible problem.

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Replacing a heater core is no more harder that changing the spark plugs, yes they are both a pain in the rear end. (Well, maybe the heater core is a tad more involved), but you get my point.

If you read and comprehend what I posted, I did say for him to check the items 1st, not just go out and buy the stuff and replace it all.

 

Kris, not that I'm taking sides here, but as a neutral party you did come across as a complete smartass to Stephen.

I can't say I wouldn't have responded the same myself.



Back ON topic however, my girlfriends car does relatively the same thing. When you turn the blower on, you have heat for about 10 - 15 seconds then it goes cold, and you have to leave the blower off for a couple minutes before your next 15 seconds of heat. This quite simply amounts to poor flow in the heatercore. Like has been said, the two things I would check first are the coolant level and whether the heatercore is clogged (however the second check isn't as easy as the first). You can take a heatercore to auto shops and they can blow it out with compressed air, but for the price they charge just junk it and get a brand new one

 

Wasn't trying to be smart. But with the info provided, fan can be ruled out pretty easily.

I just don't see how it helps when someone just responds with wrong info

 

Depending on how you look at it, it could be either or. Stephen has already pointed this out.

 

sorry for not being very clear with my problem and the fan does blow great so i might just go ahead and swap out the heater core, and the coolant is fine, and the valve on the front right valve cover what exactly does that look like? and i will go ahead and pull out the HVAC unit and double check everything there and clean it up as Krisb stated. Now on changing a heater core what all do i need to do cause ive never done one.

 

I thought you were clear.

Anyways, do a search on here about changing the heater core, already been explained many times. Follow the heater hose coming off the heater core. The valve is on the other end of one of the heater hose, it lays on top of the right valve cover.

Open your hood and look, It's real easy to spot

 

so thats what that goofy thing is lol thanks alot i really apreciate it ill tell you how it goes this weekend if it warms up a bit so i can actually go out and do something

 

Don't forget to check the heater control cable, may have come off. Just pull the pass lower dash cover, look for a cable under the dash there on the heater box.

 

bgood makes a good point. I spotted mine just the other night while was poking around under my dash. It's not that hard to spot.

 

thats the one that covers up the ecu right? and i havnt come around to do any sugestions you guys have been cold and kinda low on cash

 

well i changed out my heater core and it still wasnt blowin hot, so i checked the diverter valve and the vacuum line that was on it had no vacuum, so i ran a line off the intake and then i had heat, but then i found a leak where i didnt tighten up the clamps on the hoses to the core so i got those tight and no leak. now the vacuum line that is on the valve where does it go anyone know?
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hey my heat only blows out the vents to the winshield while in park or stopped could that be a vacuum leak on the hvac controls cause i hear hissing when i turn it on

 

Well, if you had followed my instructions/order, you could have avoided changing out the heater core, but at least you've done it, needs to be done eventually sooner or later.

And because your diverter valve isn't getting any vacuum. And I am going to say that your vacuum line is broken/clogged before the split to the diverter valve and the inside HVAC controls. I would check the lines, they are pretty brittle, I bet the line is broken or disconnected

All you have to do is follow the vacuum lines. Listen closely, you will probably here a hissing from where the line is broken. If there doesn't seem to be a leak, the line may be clogged, replace the line.

 

I changed the heater core cause it was leakin slowly when i pulled off the plastic peice around it i seen a little puddle of coolant and i could see where it was coming off the side of the heater core. The hard vacuum line that goes to the diverter valve where does it go? to the HVAC controls or should i check the soft vacuum lines on the hvac controls

 

Well, then you didn't change the heater core out for no reason. It needed to be done, that's the hard part. Now what you need to do is follow the hard line. That same line splits off to the HVAC controls, so that line is probably broken or clogged before the split. Basiclly, now your just hunting down the vacuum "leak". Only way to do it is to follow the vacuum lines.

 

hello, im in a rush right now so i didnt get to check if there was an explination on hopw to change out a heater core, how much would it cost to do and how long. so thank if you have an answer

 

are you going to do it yourself?? If so heater cores arent the expensive. You need to take the whole dash out. and then the climate control ducts and everything that attaches to the firewall where the heatercore is. Its not difficult, just time consuming.

 

WRONG! Thats the way the book SAYS to do it.

I'll done it myself, by just pulling the lower panel, reaching up, & getting the cover off & the heater core out.

 

i agree with stephen. i told my dad to LOOK! at it. well when i got back home today,k my dad says i just need to get two more bolts off and take the hoses off, then install new one. so im guessing it is the way stephen said.

 

Don't think it is easy. It's not!

It's a royal PIA! Pull out the passenger seat & it'll make it easier to lay on your back, to reach up & get to everything.

And you won't be able to see what your doing, very much. A lot of it is by feel & touch.

Trust me.....Its not fun, but its that or pay a shop $250 to put in $30 worth of parts.

 

i agree, i just got done with my heater core replacement today. started at around 11 and ended at almost 6 with everything done including cleaning up oolant stains on passenger floor. well now im happy that i dont have to worry about anitfreeze on my friends shoes. haha

 

i think i moved a door in the wrong position when i put my heater core back in.. i have dash and vent heat but not adjustable.. gonna take it out this spring when its decent out side in a few weeks.