My wife drives an 01 navigator, and i noticed last night that the front heat ducts blow lukewarm to cool air, while the rear heater blows nice HOT air. Can anyone tell me how to troubleshoot this. I suspect a sticking tepm valve or air door, but dont really know how the system works.
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
check that the thermostat is in correctly as it will cause no circulation but overheating. have a compression test done to eliminate head gasket /cracked head. There could be a blockage in the heater core but I am thinking that by passing the heater fan he has also by passed the actuator( coolant valve) for the heater core. Water pumps suffer from bad bearings and very seldom anything else. check that he hasn't blocked off the water to the heater core as well
the throwing back of the coolant is the boiling of the coolant in the block ( bad head gasket) due to lack of circulation. It may be a blocked radiator as flushing doesn't fix the blocked cores . If that is the case a new radiator is in order.
Check out the heater hoses for warmth. Both should be the same with the water flowing. If they are not, the water is not circulating.
There are 2 ways the heater can work. One style varies the amount of water flow to control the heat levels. The other uses the blend flaps in the ducts to push air flow around the heater core.
If the heater hoses are not circulating water, a part called a flow valve is to blame. Check out the autoparts sites for photos of the flow valve for your car. If you have the blend flap system, a solenoid called a "motor" is not changing the position of the blend flap in the dashes' ductwork.
Sounds like the blend door or blend motor is not functioning/opening. This door allows the heat/cold air to come in by adjusting open, closed or anywhere in-between for temp. Start there. They are usually vacuum controlled and mounted under the front dashboard near the knee board.
this problem is caused by a defective air temperature control blend door actuator motor, it is about center of dadsh in air ducting, it moves the door that diverts air for cold from ac or hot from heater, you must remove the dash to repace it, about a 15 hour job fotr a home mechanic with a factory repair manual, nearly imposs without one.
damper in duct to change air flow from heat to air is not working most probably. I am almost certain the navigator will have an actuator motor that has stripped, or the motor has gone bad this is constantly working when you use climate control to control air temperature.