You most likely have have a bad heater control valve that is limiting the flow of hot engine coolant through the heater core. The higher engine speeds when diving are pushing coolant past the restriction. It is not a complicated repair on your vehicle.
Check both heater core hoses at the firewall to feel if they are getting hot to the touch when the vehicle has idled at normal operating temperature. If both tubes are not hot, then there is a circulation of coolant problem in the heater core. The heater core is plugged
It will have to be flushed out or replaced to rectify the situation.
Also, check the blend door. If the vacuum actuator for the blend door doesn't function then it won't allow hot air to enter the cabin.
Good luck on this repair.
HEATER NOT
BLOWING COLD,NO HOT AIR FROM HEATER,A/C BLOWS HOT AIR,A/C NOT BLOWING COLD,
COLD AIR FROM HEATER,BLEND DOOR ACUTATOR CLOSED,HVAC UNIT NOT OPERATING,
http://alltypesofpartsreplacing.blogspot.com/2012/12/heater-not-blowing-coldno-hot-air-from.html
To troubleshoot this types of problem,click the link below
:----http://howtobyme.blogspot.in/2012/02/heater-blows-only-from-defrost.html
--------Go through the procedure to confirm the
issue.
------
Engine Overheats and heater
blowing cold?
http://howtobyme.blogspot.com/2011/11/engine-overheats-and-heater-blowing.html
---------
Heat blows cold on drivers
side and hot on passenger side?
http://schematicsdiagram.blogspot.com/2011/12/heat-blows-cold-on-drivers-side-and-hot.html
-----------
This will help.Thanks.
436 views
Usually answered in minutes!
×