As the title indicates I have been unable to get any consistant information in regards a diagnosis. My 02 Montero XLS, with 145K miles has heat blowing from the driver's left side dash vent, and as you move closer to the passenger side, the heat is cooler and completely cold on the passenger right side dash vent. The same applies for the floor heat. I have gotten everything from a door might be open, to heater core. Has anyone out there experienced anything like this, and what was the remedy???? I don't want to get roped into replacing something I don't need to

 

which techs? mitsubishi dealer?

 

Dealer says it might be a heater core, and two other mechanics I have taken it to say it's not the core, it is something else. Their reasoning is that if the core was bad there would be no heat at all.

 

its the blend motor very comon

 

Thanks for the info Mike, I really appreciate the assistance.

 

was it the blend door? im having the same issue.

 

or blend motor?

 

Same problem in 2001 Montero Limited. Little heat from driver vent but none on passenger. Turn on fan to max

 

Turn on fan to the max. I used meat thermometer inserted in vent. Cycle between AC and heat 115xs and voila, heat started coming out of passenger side. Blend door had gotten stuck. 100° now. Best wishes.

 

Was the blend door the confirmed fix? Did you have to replace the entire heater box or was the door replacable? Finding a good in depth parts diagram for this thing is next to impossible. My Montero should be similar, its a 2006 limited. Driver side swtiches from hot to cold and passenger side stays cold. Im pretty sure I seen the blend air door actuator move so I suspect a broken door in the air box.