My 90 ranger still has very little to no heat coming out of the vents. This is what I have done so far..

1 Replace thermostat(working properly also)
2 Full system flush with Prestone super Rad Flush
3 Blend door working properly
4 No in line hot water valve that I can see
5 Flushed heater core with water hose(water flowed through fine,no obstructions)
6 New coolant and filled to proper level
7 Temp guage not working right but upper rad hoses and heater core hoses get real hot.


The only thing I can come up with that the heater core is clogged but since the truck came with factory air goin to be a PITA to change so changing it will be last option. I am open to any other possible options....Thanks

 

Your right if the truck doesn't have factory AC....since mine does you have to pull the dash.

 

Thats the thing I dont know if that is the prob.

 

If both heater hoses are getting hot at roughly the same rate and you said when you flushed it, it flowed freely I doubt its the core. Are you 100% sure the blend door is actually moving through its full range.

Also, you don’t have to remove the dash completely from the truck, just far enough back to drop the distribution box out the bottom on the passengers side floor.

 

Yes I looked through the passenger side vent with a flashlight and moved the control back and forth and the blend door "looked" to be operating properly. Hot side closed,cold side open i think. It looked as the door was closing all the way.

 

Well replacing the core is a good day and six pack project with a friend. Its not as bad as it sounds, just time consuming. I did mine about 2 years ago. Heres the link. Should be about the same...

https://www.ranger-forums.com/forum2...96&postcount=4

 

Thanks so you think all other possible options have been tried and I have to change the core?

 

Mouse house

Is the air flowing the same through the vents when the temp control is on max cold and max hot ?

 

Not a lot of difference....When I get about 7 miles down the road i have a little heat but you will never take your jacket off or sweat.

 

LOL I saw a chev celebrity come in that had at least 30 lbs of dry dog food hidden in and behind the A/C box, the bottom of the battery chewed out, plus half the front chassis harness missing.

 

Well you've replaced the Thermostat, coolant, flushed the system and core, checked and said both core hoses are getting hot, checked the blend door and believe it to be working correctly...So only thing left is the core. You'll be able to see more once you get the box down and the core out.

 

Thanks..I got some vacation time so ill change it out then.