2001 Tundra v-8 4X4

ODEGARD

MEMBER
2001 TOYOTA TUNDRA
V8
4WD
AUTOMATIC

The heater isent working properly, little heat nothing like it use to be. Fan works on all speeds and temp. Switch works. I replaced the thermostat.
still not heating properly. I could use your help, thanks scott

Friday, November 26th, 2010 AT 5:22 PM

1 Reply

ERNEST CLARK

MECHANIC
1,730 POSTS

First, is it blowing cold on both automatic and manual?
YOu can begin by check that the heater control valve is opening when you turn on the heat as the engine reaches operating temp.

If it's good, then remove the two heater hoses and insert a garden hose to one of the hoses and turn on water. (Put pan under car and aim hose so you don't make a mess in engine compartment) If water flows freely, your heater core is good. If not, you have a blockage. Try to flush is out with water one way, then the other. If you can't, replace it.

If heater core is good, then you have either a stuck blend door or leaking vacuum line/solenoid inside the HVAC unit. You'll have to remove the unit to test these.