Swank

Hey all I have tried and tried again with the search feature and went through the "techinfo.toyota.com" service manual (PDF) version page by page looking for the answer and I cannot find the solution.

Ok. My truck has it's heater core hooked up and sometimes I get some heat but I never get alot. Today here in Denver I woke up to -10 degrees for my drive to work and my heat sucked. The heat blowing out of my rear center console heater was hot but the stuff from my dash was not.

I have a 91 4 runner 3VZE manual. I am pretty sure someone replaced the engine in this truck before I got it. There is a hose coming from the back of my engine that heads over to the temperature control valve (plastic one) that is blocked off and goes no where and I cannot find anywhere it could go.

Could someone with a good camera take some pics of these heater hoses perhaps and show the routing of these hoses? I don't think I have a Tstat or water pump issue because hot or cold my engine temps stay right where they should and the truck heats up like it should as far as I can tell.

Thanks much for the help. Tomorrow when it's light and hopefully not 3 degrees out I'll grab some pics of how mine are hooked up.

jason191918

http://www.toyodiy.com/parts/g_U_199...-GKMGEA_4.html

Anything in here help?

100_4461.jpg?t=1229400346

Here is what it looks like on my P/U

space-junk

iTrader: (1)

sweet... thanks jason... ive been meaning to ask someone for a pic of that so i can flush my heater core...
you might wanna try to flush your core too swank, unless itsw brand new...
mine blows cold ait until i get to about 30mph... even after its warm...

Swank

OK yours looks different then mine.


OK so in this pic you can see the line the previous owner had plugged with a spark plug and tucked away so you don't notice it being "fixed" that way. The middle hose is from the heater core and goes to the valve, the left (plugged hose) comes from the area where the temp sensors are at. The right hose lined up with the driver's side valve cover (3rd from the left) comes up and goes to the other half of the temperature valve. Maybe you can make sense of these 2 pics and help me out here. I'll try again when I am not so rushed to get more pics of this if need be.

Thanks

89pickupsr5

I could definitly be wrong but i think that hose that is plugged up is from the setup that around the year 94 uses. on my 89 and my friends 90 that hose isn't in the middle of those sensors. on the 94 engine i bought it is in the middle. maybe your truck has the old setup and the engine has the newer setup. on the front of your timing cover are there one or two coolant hoses coming out of your engine?

Swank

Mine has the idler/water pass through coming through the timing cover that splits 2 ways one is the large top radiator hose and the other is the about 1" hose that goes to a steel tube that runs under my intake mani. Is that the one you mean?

I do know when I went to the dealer to get a knock sensor for my truck the 1991 knock sensor had the wrong wire for the plug on my truck.

Mine is more like the one in this pic.
http://www.toyodiy.com/parts/p_U_199...MGEA_1603.html

89pickupsr5

ya i don't think that extra hose in the rear of your engine is suppose to be there. whoever did the swap must not have felt like taking the engine apart. I wish I had my truck here to look and see if that should work ok with it plugged off but i can't tell you for sure. try to find pics you'll notice the older ones don't have that hose in the middle. chances are i'll see my truck tomorrow and i'll take a look for ya if you don't find anything by then. happy hunting

p.s. thanks for that website definitly savin that. the more sources the better!

space-junk

iTrader: (1)

interesting... I have a motor from a 94 in my 90, and IIRC, that hose that is blocked off should go somewhere... i mean, mine does... ill take a look and let you know...

space-junk

iTrader: (1)

oddly enough, my truck looks more like yours not jason's...
looks like the hose that is plugged is actually supposed to be hooked up...
hope they help you get yours sorted out...
these are the best pics that i could get...

Swank

It was snowing last night so I didn't go out in the driveway to look at mine again. Today is nicer and I hope to get out there for a while to see if I can work it out.

Vooduguru

Ok so I'm stuck on the side of the road and there's red liquid spewing out of the connection that's against the firewall that looks like a D what is that line? I'm posting from my phone so I can't exactly point it out. Can anyone tell me what that is?

jht3

heater valve. toyota uses red coolant

NYChopshop

probably the heater bypass hose. Never add green coolant to your system if you have red coolant in there. Go pick some up from your stealership (at about $20 a bottle) or totally flush it and put the lesser quality but significantly cheaper green stuff in.

hgkittyhawk

Can anyone help with heater core replacement. i have most of the dash out and the heater box still wont come out. It moves around alot but that is it......................

mi_guy616

I'm wondering what you guys ever figured out on this tread. I just bought a 91 with the same problem.

hgkittyhawk

its easy now that ive done it. wats up

mi_guy616

You figured out what the extra coolant hose was for? Mine is plugged like in the pics. It seems to have no ill effects, but I'd like to know why it's there, and maybe get rid of it.

Kauaihustler

Thanx to Spacejunk for the pix. My 4runner apparently has an older motor in it cause the 2 metal lines coming from the drivers side engine compartment have no home. This is because the larger hoses on mine do not have the T connection on either of them. Any idea what the advantage of having the hoses T'd in is?

NorthernLife

I believe those 2 metal lines running down the drivers side are for the arm rest heater (between driver and passenger seat). Advantage would be the ability to supply heat to your new female companions in the rear seat, thus a reduction in clothing required to obtain optimal warmth, leading to an increase in the amount of time spent looking in rear view mirror, resulting in your yota aquiring a lightpost as a new hood ornament.

Conclusion: The removal of T connections by previous owner was done as an obvious safety enhancement due to the high level of attention said Yota was getting from the female popuation.