no thread has answered this please help?

[speak]

i have done everything the other threads said still no luck. i changed the thermostat, flushed the cooling system(the right way), checked the heater core and flushed it and it was fine. than i filled up the system and did every trick to bleed the air out of the system. also checked the heat/ ac control valve and it is working . still no heat and i'm freezing what can i do. i thought maybe the water pump but there is no sign that it does not work. it does not over heat or make noise. should i replace it still? also the rad. fan works fine. please help. thankyou

 

[turboSR5]

Well, looks like you have covered everything. All I can say is that if your heater core hasn't been bypassed (would be pretty obvious) then your heater core has to plugged solid. Your water pump is working fine if you are not overheating.

 

[speak]

the heater core has not been bypassed and i ran water thru it and it went thru with no problem. i've tried everything shorty of the water pump the runner is a 4cyl 1987

 

[speak]

you think its possible the new thermostat i put in was defected. the heat didn't work before i did that either.

 

[rook]

1. does your temp gauge indicate it is getting warm.
2. Read this. Toyota 4Runner and Pickup: Cheap Tricks

 

[speak]

the temp gauge always goes to the same place. it also runs real lean. the plugs were real light but im not loosing any antifreeze

 

[MikesToy]

Do you get heat when your vents are open (fresh) while driving?

 

[fourwd1]

you think its possible the new thermostat i put in was defected. the heat didn't work before i did that either.<!-- google_ad_section_end -->

If the heat wasn't working before, a new t-stat isn't going to affect it. The t-stat controls coolant flow to the radiator, not the heater core. Either you have a coolant flow problem or, well, is the fan working??

 

[Jed]

Hate to be Captain Obvious here, but I haven't read your other threads, so I'm not sure if you did this or not--- Have you let the vehicle reach full operating temp and then feel both lines (in and out) of the heater core?

 

[Treeman]

"checked the heat/ ac control valve and it is working"

I was having the same problem until the other day. Does the heat not work at all or just the front. Mine was working in rear but not in front, they are two separate systems. MY water control valve outside on the firewall was fine, what i did was trace it to the hot/cold air damper door under passenger side dash, the cable had been stretched out and wasnt opening the damper door. Once I made a small repair with a pair of pliers, problem solved toasty toes. Hope this helps

 

[yotatech]

I have not noticed any information on what model/year we are looking at, but when i diagnose no heat concerns the first place I look is whether I have coolant flowing through the heater core. Carefully check the in and out hoses of the heater core..they should both be warm or hot to the touch if you have coolant flowing through the core. If you do have flow then your trouble is in the area of the blend air door (in the dash and not so fun to get to) If you have one hot hose and one cold one to the heater core then your problem lies in lack of coolant flow, possible worn water pump, or plugged core. If you are trying desperately to get heat then I assume ambient temp is cold. A water pump with worn impelers may be doing just enough to cool engine but not have enough to pump through your core.

 

[the_dingman]

Ok, so far it seems we know this:

- You're cooling system is working (as you're not overheating)
- water is able to get through the core
- the bypass valve is operating.

It seems to me that the next step is to check the cable that runs from the hot/cold control to the heater box (where the core and fan are) and see if it's moving the airflow from fresh air to hot air. First off, there should be two cables running from the hot/cold control, one to the bypass, and one to the heater box. Check the other end of the one to the heater box.