Why is my 93 Ranger blowing hot air?

[Eaglespjd]

My 1993 Ranger is only blowing hot air. Even with it set to cool and the fan set to off. The fan is also not running. The faster I go, the more hot air comes into the cab from the vents. I have checked the blend door, and it is operating normally. Does this sound like a vacuum leak?

 

[RonD]

Welcome to the forum

Blend door is cable operated in 1993 Ranger, you can see the cable and blend door arm if you fold down glove box all the way

So when engine is warmed up..............and you SLIDE the temp control to HOT it gets hotter?
And then "not as hot" when you slide it to COLD?
Than means blend door is working
But maybe its not closing all the way, there is an adjustment on the cable above glove box

There is a fresh air intake under the cowl, passenger side , just in front of the windshield, you can't see it, but it would pull in air from outside engine bay, so not that hot

There should be no change in air flow with vehicle speed?

Fan speed can change with higher RPMs if alternator is failing, i.e. higher voltage at higher RPMs


Did the vehicle ever have AC?

 

[Eaglespjd]

Welcome to the forum

Blend door is cable operated in 1993 Ranger, you can see the cable and blend door arm if you fold down glove box all the way

So when engine is warmed up..............and you SLIDE the temp control to HOT it gets hotter?
And then "not as hot" when you slide it to COLD?
Than means blend door is working
But maybe its not closing all the way, there is an adjustment on the cable above glove box

There is a fresh air intake under the cowl, passenger side , just in front of the windshield, you can't see it, but it would pull in air from outside engine bay, so not that hot

There should be no change in air flow with vehicle speed?

Fan speed can change with higher RPMs if alternator is failing, i.e. higher voltage at higher RPMs


Did the vehicle ever have AC?

 

[Eaglespjd]

Correct, when I slide it to hot...it gets hotter. Then, when I slide it back to cool, it’s not as hot. And again, you’re right on the air flow, it doesn’t change, I think it just gets hotter and hotter the longer I drive and the truck is warm. So you think it might just be a matter of adjusting the cable to allow the blend door to close fully?

 

[Eaglespjd]

And no, it has never had AC

 

[RonD]

Yes, I would fold down glove box and have a look at the cable when you slide the temp control
There is a screw that holds the cable, you can loosen it to adjust the doors open and close travel

The blend door does have foam seals that can break down over the years but would leak very little air


The heater core on 1994 and earlier Rangers is easy to remove or change
And it gives you access to the blend door, not to change it but to feel if its working.
The blend door is hinged top and bottom with just a pin, top one is attached to the arm to move it
But bottom could break so door is not closing as it should, but I would expect it to "feel funny" if that happened and never heard of it happening..............

 

[Eaglespjd]

Thank you so much for the advice Ron. I’m going to give it a try later this week. Thanks again