i have a 1999 chevy blazer and the heat wont work on the floor and the air that does come out on defrost is?

Question

cold and the antifreeze level is fine.

Answer 1

When the engine's real hot at idle, feel the heater hoses where they connect to your heater core under the dash at the firewall (under the hood). With the cabin temperature on high heat, both hoses should feel hot to the touch. If not, your heater core is plugged up. If ok, then your air blend doors under your dash may not be working properly. If you've changed your engine coolant at least every 3 years, the problem is probably under your dash with the temperature controlled fans and ductwork. This assumes your engine is at the normal 200 degree F operating temperature. GM has had a problem in some cases with their "Dexcool" antifreeze not lasting the specified 5 year maintenance interval. If you've never changed your Dexcool coolant, you can suspect a clogged cooling system.

Answer 2

The first thing to determine is how hot the motor is running. The guage should be around 200-220F or 100-115C when it is at operating temperature. If the temp. does not reach this level you will need a new thermostat which is located at the end of the upper rad hose inside the housing. If the temp. is okay you will have to check the coolant for circulating. The way to tell this is to touch both of the heater hoses and compare the two temp., they should be very close in the feel of the heat. If not, you might have a plugged heater core or a pluggage inside the motor which restricts coolant flow. This would require a pressure flush or replacement of the problem component. If all this is okay, you have an air delivery problem with your AC controls which will have to be taken apart and diagnosed to see what the problem is. Most of the problems with controls on these are control heads and temp. door driver motors not working. Good luck.

Answer 3

ineffective cells in a starter? If that is gasoline injected? gasoline Pump? Coolant temp sensor? First, starters dont have cells. they have brushes and an armature. 2d, what motor vehicle previous 1988 became into carburated? None! The gasoline pump would be a sturdy dart to throw,,,,, if it didnt run in any respect. Coolant temp sensor does no longer reason it to no longer initiate because it starts while the engines chilly each and all of the time, thats only undeniable stupid. You shouldnt have only cleared those codes, they assist you to recognize whats incorrect. Dumping gasoline down the throttlebody regardless of the undeniable fact that makes it sound like there is not any gasoline stress in the lines, that they drain bypass into opposite the line while that is executed working. That isnt the gasoline pump nevertheless. this suggests while theres no stress on the line, that is finding the thank you to enable air into the line and drain lower back to the tank. that should take some photographs at beginning it, or having to offload gasoline down the intake. It takes some seconds for the stress to construct lower back up and push gasoline upto the engine. Leaky intake, gasoline regulator, call your subject, however the nice and snug button is this, your lines are draining lower back to the tank while the engines off, era. That has no longer something to do with the air filter out, till you bumped a gasoline line or section in the technique of fixing it. (And to Jenn D under me in this answer section, what the heck vehicle aspects shop did you paintings at that a gasoline pump expenses $3 hundred to 500 dollars??? became into it made up of sturdy gold? Dont know the place your from yet up right here in cleveland ohio, the precise shelf unit direct from chevy only value $one hundred seventy five and thats from the broking. to no longer point out, if it became into the gasoline pump or a clogged injector, it wouldnt run in any respect or run incredibly tough placing off codes at once that should maintain coming lower back whether they have been reset) DaveySch, must be onto some thing (2 solutions down from mine) It does look as though the lines are loosing best, and that examine ball must be caught as he mentioned. that must be a sending unit (which regrettably you are able to not get devoid of having a gasoline pump equipped into it to boot).

Answer 4

If you unscrew your heater controll and pull it out a little you may just be able to see a part that changes where vacuum hoses connect. Thay controll the little doors that direct the heater air..
your doors might not getting vacuum.. there should be little tank under the hood maybe sphere(ball) shaped.pull off the hose while thy engine is running,there should air intake at the hose .maybe a hose is cut or the vacuum was plugged cause other vacuum things leaked
I was trying to fix mine today in a 94 tahoe blazer. removed most of the dash .took out the battery tray to find a device that controlls the front lockout ,big vac. leak in the diaphram,no vac
four hours and no heater(only defrost) tomorrow I search for the vac. source and bandage my knuckles good luck...*d

Answer 5

Sounds like the Thermostat control or a thermastat stuck in the closed position for the heater core.

You were little unclear if the blower fan works. If you feel heat and no air movement try different fan speed and it could be the blower fan resistor.

Answer 6

poor circulation , bad thermostat , plugged heater core , as a test , cover your grill with cardboard and see if it gets warm , that's your thermostat that needs replacing if it does . good luck