Not blowing heat
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The first thing you need to do is check the level. Just because someone else had an issue, that doesn't mean that is your problem. There are many things that can cause no heat. Check your over flow. If it is empty, check the radiator. You are in Canada so don't add water, add coolant and the correct coolant if it is low.
gshadow325
New member
was the under dash on driver side ever removed?
is this a recently new thing?
never open the radiator cap when the vehicle is on and when its hot. you are asking for severe burns if not careful.
question you have to ask is where did my coolant go?
please put in your vehicle model, trim, and engine in your signature so other that read it can help you better.
is this a recently new thing?
never open the radiator cap when the vehicle is on and when its hot. you are asking for severe burns if not careful.
question you have to ask is where did my coolant go?
please put in your vehicle model, trim, and engine in your signature so other that read it can help you better.
Yes, the vehicle is consistently coming up to temperature and staying there. It blows hot air when driving, but blows cold air only when idling.
I spoke to a mechanic this afternoon, and he said to feel the two rad hoses to see if they are about the same temperature, or if one is hot and one is cold. Apparently if they are not close to being the same, I may need a rad flush. I checked, and they are both approx. the same temp., so he said to add coolant to the system once it has cooled down and monitor the situation over the next few days.
I spoke to a mechanic this afternoon, and he said to feel the two rad hoses to see if they are about the same temperature, or if one is hot and one is cold. Apparently if they are not close to being the same, I may need a rad flush. I checked, and they are both approx. the same temp., so he said to add coolant to the system once it has cooled down and monitor the situation over the next few days.
"Was the under dash on driver side ever removed??"
Funny you should ask that.
I just did an install for an aftermarket radio and when I put everything back, I was only getting heat out of the driver side. Still blows on the passenger side, but only barely warm air in heat mode and ice cold on defrost.
Is there something that could have been jostled under the dash when I was putting it back together?
Before the install, everything worked like new.
06 SR5 4x4 82k miles.
99% sure you're just low on coolant - that's a good thing!
JEL
New member
Sounds like a classic case of shitty Toyota climate control actuators. A quick web search will net you an endless supply of actuator failures in Toyotas, my 3rd gen had one go bad, and my 4th gen probably will need one soon enough. It's holding up now since I smacked up under there a couple months ago, but it'll probably stick again.
BlackWorksInc
New member
Honestly we haven't seen that many actuators going bad lately... the only ones have been newer Siennas because people somehow shove quarters into the vents and they magically end up in the HVAC box and jam up the door which breaks off the shaft for it...
Record so far is something like 63 cents I saw sitting in all the vents, probably more in the HVAC box; but the customer didn't want to pay to fix it...
Just for your knowledge, you can start a cold engine with the radiator cap off, otherwise you can't really burp the system properly.
The never ever huge no no is taking that cap off after you've already started and the coolant is hot, unless of course you want your skin on face burned off.
[MENTION=66389]BlackWorksInc[/MENTION] please correct me if I'm mistaken, but I've burped my coolant of air pockets with the radiator cap off. How else would you do it?
BlackWorksInc
New member
Well you could do it with the cap on, it'll just suck the reservoir dry if there's too much air in the system. What we normally do is use a funnel like this:
as it lets you overfill the radiator and watch the bubbles come out, then I'll usually use what's left in the funnel to put the reservoir to "Full" and whatever smaller air bubbles may be left usually bring it down to a more normal level.
We like to put the heater on low as some older vehicles actually had coolant switching valves for the heater. But I don't believe most modern Toyotas do.
gshadow325
New member
you know i said when the vehicle was HOT. thanks for blessing me with your knowledge.
You may want to look at the way the cooling system works. There is no such thing as 'burping' a system. Hot coolant enters the top of your radiator and cool coolant exits the bottom. Gravity keeps air at the top and it will not cycle back through unless you are extremely low on coolant. The device that blackworks shows is nothing more than a reservoir of additional coolant so that you can top off a radiator by yourself. You can do the same thing by standing over your radiator with a jug of coolant while your partner revs the engine.
As for removing the cap, unless you are running 100% water in a car from 1972, you can easily remove a cap without danger from a car operating at normal temps. You wouldn't want to do this with one that has over heated because you could get blasted with steam. Under normal operations the coolant remains a liquid. A properly working cap will build pressure, but as you release the pressure any over flow will return to your over flow bottle
BlackWorksInc
New member
I would say it's not as bad if the vehicle has overheated... but keep in mind that the coolant by it's nature is designed to be under pressure specifically to raise it's boiling temperature, so it's going to be HOT and when you take off that 14~15psi of pressure it's under the boiling point drops instantly.
On a normally operating cooling system it will create a puff of steam (as the boiling point drops instantly) and a surge of coolant as the water pump is circulating it. It won't erupt like Pompeii, but it will catch you by surprise if you're not paying attention and leave you with some burns on your hands and possibly face if you're smart enough to be that close to it (if you use a rag make sure you use a few of them). (I had the unfortunate luck to be working on a pile of crap BMW when a bleed plug failed on the radiator, the combination of loss of pressure and circulating coolant was enough to spray it in the air where my face happened to be near by... had a lovely half-burned face for a good few weeks while it healed up...)
On a normally operating cooling system it will create a puff of steam (as the boiling point drops instantly) and a surge of coolant as the water pump is circulating it. It won't erupt like Pompeii, but it will catch you by surprise if you're not paying attention and leave you with some burns on your hands and possibly face if you're smart enough to be that close to it (if you use a rag make sure you use a few of them). (I had the unfortunate luck to be working on a pile of crap BMW when a bleed plug failed on the radiator, the combination of loss of pressure and circulating coolant was enough to spray it in the air where my face happened to be near by... had a lovely half-burned face for a good few weeks while it healed up...)
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nevada
Senior Member
some engines/systems are worse than others for trapping air. some even have a bleed valve installed specifically for bleeding/burping the air, because the design traps it.
and you most definitely want to be careful opening a hot radiator. as blackworks said, its under pressure, suddenly releasing that pressure, and sending that 16psi, 200ish degree coolant spraying all over can be bad...
ALWAYS squeeze a radiator hose to check for pressure prior to opening a cap. if the hose firm, DONT open it.
same thing happened to me. the other guy I was working with popped the cap, and boiling coolant sprayed me right in the side of the head. burned my ear badly, and the side of my head and face.
You do work on cars and are not a lot attendant, right? J/k
The boil over point of a 50/50 mix is about 225 degrees @0 psi and around 250 @15 psi. Your engine operating temperature is somewhere around 180-190 degrees. You will never boil over at that point. Add in the safety designs with caps on modern cars and it becomes even safer. The way that caps are designed you have a double seal so that when it heats up it will build pressure through thermal expansion and draw coolant back into the system as it cools. When you remove a cap, you can't remove it in one step. You first release the pressure then have to push down to actually get the cap off. The initial release sends any pressurized fluid back into the over flow instantly, and because you can't compress fluids, 12psi of compression will yield slightly more than a few ounces at best.
Of course all bets are off if you have overheated the engine, and if you have ran it up above 250 degrees, coolant will probably be the least of your concern.
nevada
Senior Member
you assume the cap is working as designed.
I have seen it many times where it blows coolant everywhere upon removing the cap. after having your face burned, you tend to be a bit more careful...
BlackWorksInc
New member
No I'm a technician (at least that's what my paycheck says
), I just got unlucky with that BMW as I had just used the bleeder and snugged it after bleeding the system and I was looking for leaks. Those plugs are ridiculously fragile after only a few years and it decided to give up the ghost just as I was looking into the engine bay; sort of a glancing blow but the coolant and spray was enough to leave a nice horror movie looking burn on my face for a few weeks. :repuke:Depends on the system to be honest with you. The reservoirs on some of the Toyotas where they have the cap integrated into them are more forgiving as when you loosen them they bleed pressure much better than the metal caps on the radiator. Most of the metal caps I've noticed don't bleed pressure into the reservoir until you start to remove the cap, just twisting it to the stop before pushing down and turning doesn't release pressure on most of them.
Like I said, it's not going to make a geyser like it used to back in the day; but you can burn your hands a bit if you're not careful as it will bubble up/spurt out around the cap when the pressure is released and you take the cap off. But nothing a handful of rags and slowly turning/lifting the cap off can't fix.
As for the funnel, it's technically just an open reservoir; you can use the reservoir to burp the system in the same way. The only difference is that with the funnel you can watch the bubbles coming out of the system much easier.
