heater problems

RonLange · 10-06-2005, 11:53 PM

93 regal GS
OK, i don't get it. i've had heater problems, so i replaced what was a restricted heater core, replaced the thermostat, and refilled and bled the cooling system. the heater was fine for a bit, but as soon as i got on the highway, the heat dropped off and won't come back. the engine temp. is working fine. this is a variable airflow heater, not a variable water flow heater and i simply don't know what to do next. the ductwork "appears" to be working fine, but i don't really know how it should look when it is working right. what the ___ is wrong with this thing? grrr...

**guyopel** · 10-07-2005, 05:21 PM

Your eng. is prone to coolant lock ( air in the cooling sys. ) you will need to run car until temp. goes up , then shut car off let cool for app. 15min. then add coolant then
restart and let car heat up then cool again adding coolant when in cooling cycle. This should be done with the cap off the res. tank and will take time .
Hope this helps. Guyopel

RonLange · 10-09-2005, 11:38 PM

i did bleed the system through the bleed screw on top of the thermostat, but apparently that isn't enough.
are these things really that hard to bleed the air out of?

**guyopel** · 10-10-2005, 07:01 AM

Yes they are a pain !! The bleed screws you found are only good for the first step in getting air out of the sys. when you first fill the coolant sys. after repairs , the method I recomend was after you fill the sys. cold .
Hope this helps. Guyopel

RonLange · 10-10-2005, 06:25 PM

well ya, i spent all day bleeding air out of the system, but still nothing from the heater, the hoses are both hot as they should be, the engine temp. works great, i just dunno, must be something in the ductwork, wish i knew more about how this things airflow works.

RonLange · 10-11-2005, 08:14 PM

i think i'm gonna sniff out a possible vacuum control problem with the blend door, sound about right?

**jimst45651** · 02-21-2007, 09:04 PM

my 1987 buick century heater is blowing ,kinda of warm air not the air the thermostat calls for 195*,,and it seems when I drive it even a long time its the same,still very small amount of heat,,something is blocking the heat from flowing to heater core I think,,and ain't there a valve on them called heater control valve,, which is suppose to open up when water heats up to 195*,, and circulate thru it,,stumped at this point,,,

**Rusty** · 03-14-2007, 07:31 PM

so i replaced what was a restricted heater core

Tell me it wasn't the good old "stop leak"that was blocking your heater core...if it was try to pull both the hoses and flush it,that stuff is really bad for hanging around and showing up right after you replace a heater core,it's like tar.