Heater/A.C. issue

[Guju Rider]

I recently that when the air is blowing at 60 degrees (doesnt matter if its the heater or a/c) the air is cold, but just as soon as i go to 61 degrees the car starts blowing hot air as if it were at 90 degrees...so basically anything from 61-90 degrees feels all the same. This happens even if i have the a/c going, 61 is ballz hot and then 60 starts throwing out 60 degree air. I check the coolant and even left the radiator cap open for a few minutes when I first started the car in the day time and it still happens.

[joe603]

That's a new one...can you control it manually?

[Guju Rider]

i checked the coolant level and they are good..the only issue i found was there was no cap on the resivoir (which im pretty sure has no effect on anything). But still having a problem with the temp...i can put anything between 61-90 (manual or auto or econ...inside air or outside) and still feels like 90 degree air blowing out...but just as soon as i put it to 60 (manual or auto or econ...inside air or outside) then you can feel the cold air...which is actually 60 degrees..but whenever switching from 60 to 61-90 the air blowing out dips down (as if it was on the lowest speed) and goes back to wherever it was at....with spring and summer coming up...i'd like to get it fixed so i can run the 72-75 AC temps..