Rear heater not blowing heat

[colorado4runnin]

So I have 99 4Runner I bought used. With the rear heater. But I have found the rear heater will not blow hot air. Just air on both high and low settings. And yes I have made sure the temp setting is on hot. So the question is has anyone come across this issue and what are some possible solutions.

Thanks,

Jake

 

[nor_cal51501]

Jake [MENTION=99762]colorado4runnin[/MENTION], that is actually a pretty common issue. Have you checked the coolant lines under the cab to see if they are/have leaked or rusted through? The rear heat has separate lines from the main heater core. Heres a post on someones fix, assuming thats your problem as it seems to usually be.

http://www.toyota-4runner.org/3rd-gen-t4rs/117187-coolant-leak-rear-heater.html

 

[TheDurk]

It's likely the coolant lines to the heater were disconnected at the firewall in the engine compartment and the supply return lines looped together due to failure of the lines under the truck.

You don't need hard lines. You can probably cut out the corroded leaky tubes and replace with rubber coolant hose.

 

[colorado4runnin]

I have glanced at them, if it is leaking it just didn't catch the eye. If they are leaking, that would cause it not to blow heat??

 

[colorado4runnin]

It's likely the coolant lines to the heater were disconnected at the firewall in the engine compartment and the supply return lines looped together due to failure of the lines under the truck.

You don't need hard lines. You can probably cut out the corroded leaky tubes and replace with rubber coolant hose.

I will have to take a look at that in the morning. Can't be that hard to replace those lines?

 

[nor_cal51501]

I will have to take a look at that in the morning. Can't be that hard to replace those lines?

Naw, most people say it takes less that 30 minutes to do the actual R/R.

 

[colorado4runnin]

Naw, most people say it takes less that 30 minutes to do the actual R/R.

Rite on! Well I ran out there and found those lines don't look pretty at all. Now question is there should be two lines running into heater from under the car? Correct?

 

[nor_cal51501]

Yes, there should be an in and out. One supplies fluid into the rear "core" while the other is a return.

 

[colorado4runnin]

Thanks guys, I'll replace those lines and see if she will blow heat.
Thanks again,
Jake.

 

[nor_cal51501]

Keep us posted on how it goes. Good luck Jake.

 

[Gerdo]

Before you replace the lines, find where the rubber lines meet the metal ones. Pull them off and see if you have flow there first. Then take a hose and see if you can get flow thru the heater core.

I haven't even looked at mine. What controls the heat? Is there a heat diverted valve? Is that moving/opening when you move the heat lever?

If there was a leak, you would be losing coolant.

 

[colorado4runnin]

Before you replace the lines, find where the rubber lines meet the metal ones. Pull them off and see if you have flow there first. Then take a hose and see if you can get flow thru the heater core.

I haven't even looked at mine. What controls the heat? Is there a heat diverted valve? Is that moving/opening when you move the heat lever?

If there was a leak, you would be losing coolant.

Yeah I'll try that, if there is a leak then it's not very noticeable because those lines are so small, but I'm going to see if I can push water though the core and see what crap will come out. I'll keep you all posted on what happens and what I find

 

[TheDurk]

Yeah I'll try that, if there is a leak then it's not very noticeable because those lines are so small, but I'm going to see if I can push water though the core and see what crap will come out. I'll keep you all posted on what happens and what I find

First question is whether they are hooked up at all. They can't leak if they're not hooked up...until they are.