My car's heat is very weak. It seemed to blow pretty warm in the summer, but now that the cold weather is here, it blows barely warm. Air comes out of the vents just fine, it is just not hot air.
My coolant level is fine. I have made sure that the switch under the dash is open. My temperature guage on car always seems fine, never seems out of wack. And after doing an engine swap, the situation remained the same. Didnt get any better or worse. What can this be??

 

maybe the heater core that air its supposed t go tru and warm up its a lil clogged.,
see if u can clean it.....

 

I doubt this is your problem, but if you have a/c turn the a/c button off when you run heat. I had many cold mornings to school like this till my friend turned the button off and it got real hot quick.
Stupid me
and I'm sure its funny too

 

I dont have A/C or A/C button.

I have heard about the heater core before....located somewhere under the dash/firewall? I didtn think that this being clogged would be the problem however, because it does blow plenty of air, its just not hot.

I was wondering...... could i take the two coolant hoses that run to the firewall and switch them around? Have the coolant run in backwards to maybe flush out the heater core and release a clog? I have never heard of thsi before though, and i dont wanna send coolant all over the inside of my car.

 

well the heater core itself is under the dash, but coolant from your engine goes to it for the heat, hence the term heater core. the vents blowing and stuff is another story. on the firewall, you will have i believe 2 tubes coming out of it with hoses that connects it to the engine. just flush that out properly and you should have heat again

 

Heres what you do to find out if you have a clog in your heater core...Locate both of the hoses that go into your car (there right next to eachother) grab onto one after the car is warmed up for a bit then right after that grab onto the other one. If one hose is hotter than the other your heater core is clogged and for the most part you wont be able to just clear a clog is probably corroded (which was my case) so which means new heater core which is a royal PITA!!!

I got mine from Autozone for like $90 or so bucks BUT the thing didnt line up right!! I had them order me like 4 of them and I finally got fed up and "made" one work by pushing and pulling on those damn pipes im just glad I didnt break it cause they break extremely easy!! I would say best bet is to go to the junkyard and pull one from there sure its used and wont last as long as new but new OEM ones are like $300 bucks!! And IMO its not worth the trouble getting an aftermarket one.

But yeah grab one hose then grab the other and see if there is a temp difference. OR a lot of radiator places will even test it for free. One other thing you could try (which worked for a bit for me) is to disconnect both the hoses as stated above and then use a hose and try to put it on one side very tightly and crank u the water that should free up some junk that may be in there. I did it got heat back but only for a little while then it was back to no heat again.

 

Check to see if the heater control valve is being opened all the way. The cable goes to the valve on the firewall just behind the throttle body. Have some one turn the heat control all the way up then all the way down. watch the valve. i would bet its just not opening all the way. just remove the clip holding the cable jacket with the heat control all the way Hot make sure the valve is open all the way then reclamp the cable jacket. If it does not heat then check for clogs in the piping and heater core. its a real pain to get that heater core out!!!

 

i had the same problem and it ended up being my climate control box.......... since it basically was cracked in half where the rexs' usually do. installed an new CControl and it worked better but not the best, couple weeks late my headgasket blew......... i hear lack of heat is a sign of a bad headgasket but since u swapped the motor it shouldnt be that.

 

First make sure that the control cable is moving freely on the Climate Control. Then, find the control vale on the firewall where the cable comes out. Watch as the ****/slider is moved. The valve can get stuck or be unable to open fully.

 

AS i stated in my orginal post, i have checked the temperature control vavle, and made sure it was on heat. Thats NOT the problem... I will check on the two hoses being the different temperatures.
I dont understand that though? The hot coolant is going in one hose, INTO the heater core, and getting blocked by a possible clog??? HOw does it return back to the motor? Does it just back flush, and the second hose has no fluid running through it??

 

It will still circulate through the block and such it just wont go through the heater core itself if its blocked/clogged.

 

i'll bet its the cable. happends to a LOT of EFs. the cable like to slip off the mechanism arm. look for it under the dash, above the passenger's left foot area.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Eggman &raquo;</TD></TR><TR><TD CLASS="quote">i'll bet its the cable. happends to a LOT of EFs. the cable like to slip off the mechanism arm. look for it under the dash, above the passenger's left foot area.</TD></TR></TABLE>

For the third time, IT IS "NOT" THE CABLE!!!

I let the car warm up a bit..... Top radiator hose was getting warm, bottom wasn't, and both of the smaller hoses going to firewall seemed equally warm. So...? NOw I am lost again.

 

hey, maybe its the cable, happens all the time... hehe

i actually have the same problem, i know its the heater core being clogged, probably from corrosion. i think me switching from green to orange coolant was the problem, i found out later that was not a smart move. im just too lazy to pull the dash and swap the core, especially since i have a rollcage...

 

[QUOTE=Tyson]hey, maybe its the cable, happens all the time... hehe

[QUOTE]

Ight cool, i'll check that out, thanks man.

Definetly not gonna pull out my dash... so i guess my only option is to try and back flush it with a water hose.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sick hatchem &raquo;</TD></TR><TR><TD CLASS="quote">I let the car warm up a bit..... Top radiator hose was getting warm, bottom wasn't, and both of the smaller hoses going to firewall seemed equally warm. So...? NOw I am lost again.</TD></TR></TABLE>
Well first how long did you let it warm up for?? Cause sometimes it takes a bit for the thermostat to open up which is why the hoses (upper and lower raditor hoses) might now have been the same temp. And that also could be why the heater hoses on the firewall were the same temp.

 

the heater hoses into the heater core are going to be the same temp anyway if the heater core is clogged because there is no checkvalve in the system, so the coolant in both tubes are going to mix with the hot coolant.

geez, why wont you guys just accept that the heater core is clogged.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tyson &raquo;</TD></TR><TR><TD CLASS="quote">

geez, why wont you guys just accept that the heater core is clogged. </TD></TR></TABLE>

When did I NOT accept this? Just wanted to get some sort of constructive feedback on the situation before i started tearing my car apart in the 45 degree weather we are having

Anyhow, tonight, all of a sudden, i have luke warm air back. So i dont know what is up, it comes and goes. I guess the next opportunity i have i will try to disconnect the heater core hoses and blow through them with a hose. Is there a certain direction i should aim the hose through?

 

dude, im not talking about you. im talking about all the ppl who keep telling you to check the hoses.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tyson &raquo;</TD></TR><TR><TD CLASS="quote">dude, im not talking about you. im talking about all the ppl who keep telling you to check the hoses.</TD></TR></TABLE>
OK first off your wrong when mine was bad there was a noticable difference in-between the heater hoses dont believe me?? I dont really care I am going by experience not hearsay.....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sick hatchem &raquo;</TD></TR><TR><TD CLASS="quote">Anyhow, tonight, all of a sudden, i have luke warm air back. So i dont know what is up, it comes and goes. I guess the next opportunity i have i will try to disconnect the heater core hoses and blow through them with a hose. Is there a certain direction i should aim the hose through?</TD></TR></TABLE>
Yeah mine would do the same thing from time to time I would get some heat then I wouldnt....As for which way to try and flush it try it both ways actually that way your flushing it the way the coolant flows and also the opposite of the way it flows.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tyson &raquo;</TD></TR><TR><TD CLASS="quote">dude, im not talking about you. im talking about all the ppl who keep telling you to check the hoses.</TD></TR></TABLE>

Yes i know that, thanks.

I will try backflushing both ways Vince, thanks for the advice