HEATING PROBLEM IN MY 1ZZ.

[JJCRU23R]

GDAY,

dont know why i didnt ask about this earlier...

its been cold in sydney in recent weeks and in the last 5-6 weeks Ive had problems getting warm air out of the fan. It simply doesnt warm up. Before any problems occured, i had the opposite problem, meaning that if i had the air turned even half way between cold and hot, the air would be more than warm enough to keep everyone in the car toasty.

all that works now is the fan and airconditioner.. but no warm air which has become a real issue lately. it was my understanding that the warm air comes from the warmth of the engine so actual heater involved... please correct me if im wrong on this.

anyway, if you can help me out, tell me where I should be looking for problems, my wife n kids would greatly appreciate it.

Jase.

[DJKOR]

Now I'm not sure about how the 1ZZ takes care of it's heating so I'll explain two scenario's. You are right in that the heater relies on the engine heat. In cars, a small coolant line (using the same coolant as the engine) runs into the car, through a heater core, then back out to the engine bay.

Some cars have a tap on that coolant line going to the heater core so that depending on how much heat you adjust to, the tap adjust proportionally. If your car uses this method, then the issue may either be in that tap itself, or a blockage in the coolant line.

Other cars have fixed flow though the heater core at all times and therefore don't have a tap to restrict flow of coolant. In this case, the heater core is isolated and closed off with a vent. When you adjust the heat on the dials, the vent is opened up in proportion to allow more or less flow past the heater core. In this case, the problem could lie within the vent adjustment (newer cars have servo motors, so that is a point of failure), or it could also be a block in the coolant line.

[Blind Kid Seeks]

Pray to god it isnt the heater core.

I swear, that when they build cars, they start with the heater core, and put everything around it.

[cuppas]

haha +1 sacrificing lambs to prevent heater core replacement

[123R-Prozak]

lol omg heater core omg if its that... not fun to be u :P.. umm dunno if these have heater taps if its operated off vacuum or solenoid, id be playing with the dial and checking the heater tap if it does anything... pull the lines out of the engine bay and check if their blocked... also.. you dont have the a/c on when you want heat do you?? cause it wont be as warm if you got the a/c off, have it off and just the fan going with the heater...

Edited June 21, 2009 by 123R-Prozak

[JJCRU23R]

yea i just read the corolla manual i bought way back when i did my first oil/filter change.

it said it could be any number of things, including:

A. stuck thermostat

B. blocked pipes

C. stuffed heater core. - this involves removing steering column and the whole dash!

im betting its the thermostat! thats an easy fix, right?! my 03 1zz has only done 63xxx kms so far?! surely it cant be the core! damn it if its the core ima make sure they relocate that to the glove box or something this is rediclous.

Edited June 21, 2009 by mannyMANNYmanny

[DJKOR]

it said it could be any number of things, including:

A. stuck thermostat

B. blocked pipes

C. stuffed heater core. - this involves removing steering column and the whole dash!

Someone correct me if I'm wrong, but a stuck thermostat would mean that your temperature needle on the dash would be reading colder than usual. On top of that, you would be getting at least some warm air if you turned the head dial up to full as your car wouldn't be running absolutely cold if the thermostat was stuck. If neither of those are happening, I would be suspecting that it isn' the thermostat.

Like I said though, I may be wrong.

If you had the resources, I'd be aiming to remove the coolant lines going to the heater core (in the engine bay) and trying to connect a hose to it to see if you get any flow though it.

[Guni]

what's with the heater core??

[JJCRU23R]

damn i forgot bout that djkor i think your right on that point... the thermostat is sorta linked to the temperature dial in the console yea? i havent had any temperature issues, so im thinking now it may be a blockage. there was one time the other week we drove down the m7, then the m5 to go to sutherland shire, which is 40-50 minute drive from my place. the heater was set all the way up and there was SOME heat coming out but it was erratic.. not steady, continuous or strong as it has been in the past. im hoping its only a blockage of the pipes... instructions for that is also in my manual...

i saw all the work that goes into removing the heater core (in pictures).. the manual said its not reccommended to fix at home since youre dealing with areas around the airbags.

damn this doesnt look good.

anyone know how much it would cost to fix if it was the worst case scenario ? from memory the thermostat would have been like 100 to replace by a mechanic.. but with all the work involved with replacing the heater core.. damn.. im not too sure i want to hear the quote...

Edited June 21, 2009 by mannyMANNYmanny

[JJCRU23R]

2 car pros

just checked the website above, first thing it mentions as reasons for heater failure is that the coolant may be low, which in my case could be true... since the coolant last time i checked is around 3/4 or half way full.

Ill give that a go and see what happens before i go to work..

[DJKOR]

damn i forgot bout that djkor i think your right on that point... the thermostat is sorta linked to the temperature dial in the console yea?

I'm not 100% with my car knowledge, but I thought the only thermostat was the one that controls coolant flow to the radiator. I didn;t think there were any others.

just checked the website above, first thing it mentions as reasons for heater failure is that the coolant may be low, which in my case could be true... since the coolant last time i checked is around 3/4 or half way full.

Checking your coolant level by the actual coolant reservoir is not an indication of low coolant in the radiator. When the engine is hot, you may find that the coolant in the reservoir may be towards the full side, but when cold, it may be towards the half-way point. If your coolant reservoir looks like that, chances are that your radiator is 100% full and low coolant is not an issue.

[JJCRU23R]

when i checked the coolant level, the car was cold.

in any case, ill fill up the coolant in the morning, then check those hoses after i get home from work.

might also be a good idea to check the fuse box.. heater fuse? tempted to check it now but im still doing work on some year 9 reports.

Edited June 21, 2009 by mannyMANNYmanny

[JJCRU23R]

UPDATE.

right now i am at work. this morning I filled up my radiator with more coolant. looks as though the coolant level was much lower than first thought.

anyways, on my way to work my car begins to OVERHEAT. I had to stop twice, hoping that the temperature would go down, but for the majority of the drive the temp was upto/close to the RED!

now tell me in your experience what this might be? i had a smiliar problem with my bundera and it was the thermostat that needed to be replaced.

any other hypothesis's guys?

Im lucky i only live 10-15 mins from work.

jase.

[Blind Kid Seeks]

ok.. pull back your carpets in the passenger and drivers footwells and check for moisture.

if you have cracked the heater core, they leak IN the cabin.

so check for moisture everywhere under the dash, carpets, kick panels.

just to give you a bit of an insight.... heres a quick picture of the halfway point when we pulled the heater core from my AE92.

[JJCRU23R]

just checked - no moisture to speak of BKS... this is no longer just a heater problem.. the car itself is overheating up to the red.

i still suspect its the thermostat... hopefully i can drive home without the engine blowing up.

Edited June 22, 2009 by mannyMANNYmanny

[DJKOR]

just checked - no moisture to speak of BKS... this is no longer just a heater problem.. the car itself is overheating up to the red.

i still suspect its the thermostat... hopefully i can drive home without the engine blowing up.

If it is your thermostat causing your engine to overheat, then you have two problems on your hand. If you were to have full coolant in your cooling system and the thermostat was stuck closed, yes your engine would overheat, but if you turn your heater up to full, you should have some damn hot air.

Did you actually check the level of coolant in the radiator itself, or just the overflow tank? If I were you, I'd wait till the engine was cool then take off the radiator cap and look at the level of coolant in there. It should be up to the top.

[JJCRU23R]

Did you actually check the level of coolant in the radiator itself, or just the overflow tank? If I were you, I'd wait till the engine was cool then take off the radiator cap and look at the level of coolant in there. It should be up to the top.

thanks man i havent been thinking straight. i knew the little indicator window was only for the overflow, but in all my confusion i had mistaken it for the actual amount of fluid in the radiator. in my previous car, the engine looked mighty different... the plastic radiator overflow was white/translucent and was very obviously separate to the actual radiator. since the overflow and the actual radiator cap on the corolla are so close together, and apart from the different caps the tubes appear to be all black plastic, ive gotten things confused. cant believe i made such a stupid mistake. id have never made this mistake in my previous car.. everything seems pretty obvious in my bundera since it was an 1985... moving up to a 2003 everything seems plastic in the engine bay.

anyways my dad checked out the car and i ran the engine, opened up the correct radiator cap and poured as much radiator fluid as possible. i cant believe ive been just filling the overflow all this time! within the space of only 15 mins, the engine temp had stabilised and the heat has returned to my airvents.

ive taken the car out for petrol and the car runs fine.

thanks everyone for your help!

[DJKOR]

That's good to hear that your problem could be resolved like that. It's much easier than if it were a bit more serious.

Just keep an eye on the levels over the next week to make sure it's not loosing coolant. If it does appear to be losing some coolant, then may be a leak from somewhere. Hoses can wear over time, so if there is a minor leak in one of them, it may be good indication that it's time to inspect them and change them if necessary, or maybe even tightening of a hose clamp.

Either way, it's good that you have found the solution.

[CHA54]

if I was you I'd be trying to find where the leak is, it's uncommon to lose more fluid from the cooling system than your overflow bottle can deal with.

[mbruce]

Too right! Your not out of the woods just yet, as you must have a problem of some sort in the cooling system. Like CHA54 said, You should never loose more coolant that what you reservoir can handle. In fact cars these days don’t usually consume any coolant as such.

Edited June 23, 2009 by mbruce

[JJCRU23R]

im pretty sure its a case of me filling up the overflow and not the actual radiator.

It has been several days since I have filled up the radiator proper and I have not had any issues since. The day after I filled up the radiator, my car would bubble or "gargle" briefly.. must be simply air bubbles in the coolant. I have not had any problems and the temperature has not gone even half way up since monday. will be topping up oil and coolant on the weekend. there was never any sign of any possible coolant leaks. it was just me filling up the radiator wrong.

its soooo good having the heat back in the cabin during the cold drives to work!

[Blind Kid Seeks]

im pretty sure its a case of me filling up the overflow and not the actual radiator.

It has been several days since I have filled up the radiator proper and I have not had any issues since. The day after I filled up the radiator, my car would bubble or "gargle" briefly.. must be simply air bubbles in the coolant. I have not had any problems and the temperature has not gone even half way up since monday. will be topping up oil and coolant on the weekend. there was never any sign of any possible coolant leaks. it was just me filling up the radiator wrong.

its soooo good having the heat back in the cabin during the cold drives to work!

the fact tht you had to put fluid back in the radiator is a pretty obvious sign of a coolant leak to me.