No Hot Air
Thread Starter
Safety Car
Joined: Feb 2000
Posts: 3,771
Likes: 0
From: MANDEVILLE, LA La
No Hot Air
My 95' will not put out hot air when I turn up on the thermostat.Cold only.Is there a Heater control valve might not be working???
Is it PCM controlled???
Help..
Thanx
Blue Nose
Is it PCM controlled???
Help..
Thanx
Blue Nose
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
I have two suggestions, and would like to know if you had heat and when.
1) The door which blends the air for temperature is not moving for some reason. The clip could have come off or motor not being driven + some other reasons. You can look at the door by removing the motor controller which is on top of the air box under the hood (3 screws). Look in and try to control
2) Heater core is plugged up. Hoses must be as hot as other hoses on engine when engine is at temperature. Remove hoses and flush with garden hose if need be.
1) The door which blends the air for temperature is not moving for some reason. The clip could have come off or motor not being driven + some other reasons. You can look at the door by removing the motor controller which is on top of the air box under the hood (3 screws). Look in and try to control
2) Heater core is plugged up. Hoses must be as hot as other hoses on engine when engine is at temperature. Remove hoses and flush with garden hose if need be.
Le Mans Master
Joined: Jul 2001
Posts: 8,183
Likes: 3
From: Santa Maria, CA
Have a look under the passenger side injector cover on the engine. Under there (somewhere) is a check valve that supplies vacuum to the climate control system. That plastic check valve usually gets brittle and breaks leaking vacuum.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
There is no heater control valve on the '95. Coolant flows to the core at all times.
Temp door in the Evaporator Case is controlled by an electric motor (Electronic Air) or a cable from the Dash Controls (Manual Air). Vacuum is only used to control the position of the doors that determine whether air is blown from the vents, heater outlets or to suck in outside air.
You can view the temp door as previously described by removing the Blower Module (Electronic Air) or Resistor Pod (Manual Air) on the left side of the Evaporator Case mounted on the Firewall. Have someone operate the controls and verify that it moves. If not, it's linkage is connected to the motor that controls it (Electronic Air) with a plastic clip and that clip has probably broken or the cable (Manual Air) has snapped. Access to the motor or cable is from the passenger's compartment - remove the hush panel.
If the door is working, the core is probably plugged up. When that happens, coolant flows over the top of it, but not through it. Try water from a garden hose or compressed air to flush it out. Go easy on the compressed air - normal coolant pressures are usually 15 to 17 psi. If you can't get it unplugged, you'll need to replace it.
Temp door in the Evaporator Case is controlled by an electric motor (Electronic Air) or a cable from the Dash Controls (Manual Air). Vacuum is only used to control the position of the doors that determine whether air is blown from the vents, heater outlets or to suck in outside air.
You can view the temp door as previously described by removing the Blower Module (Electronic Air) or Resistor Pod (Manual Air) on the left side of the Evaporator Case mounted on the Firewall. Have someone operate the controls and verify that it moves. If not, it's linkage is connected to the motor that controls it (Electronic Air) with a plastic clip and that clip has probably broken or the cable (Manual Air) has snapped. Access to the motor or cable is from the passenger's compartment - remove the hush panel.
If the door is working, the core is probably plugged up. When that happens, coolant flows over the top of it, but not through it. Try water from a garden hose or compressed air to flush it out. Go easy on the compressed air - normal coolant pressures are usually 15 to 17 psi. If you can't get it unplugged, you'll need to replace it.
7th Gear
Joined: May 2006
Posts: 7
Likes: 0
Originally Posted by SunCr
There is no heater control valve on the '95. Coolant flows to the core at all times.
Temp door in the Evaporator Case is controlled by an electric motor (Electronic Air) or a cable from the Dash Controls (Manual Air). Vacuum is only used to control the position of the doors that determine whether air is blown from the vents, heater outlets or to suck in outside air.
You can view the temp door as previously described by removing the Blower Module (Electronic Air) or Resistor Pod (Manual Air) on the left side of the Evaporator Case mounted on the Firewall. Have someone operate the controls and verify that it moves. If not, it's linkage is connected to the motor that controls it (Electronic Air) with a plastic clip and that clip has probably broken or the cable (Manual Air) has snapped. Access to the motor or cable is from the passenger's compartment - remove the hush panel.
If the door is working, the core is probably plugged up. When that happens, coolant flows over the top of it, but not through it. Try water from a garden hose or compressed air to flush it out. Go easy on the compressed air - normal coolant pressures are usually 15 to 17 psi. If you can't get it unplugged, you'll need to replace it.
Temp door in the Evaporator Case is controlled by an electric motor (Electronic Air) or a cable from the Dash Controls (Manual Air). Vacuum is only used to control the position of the doors that determine whether air is blown from the vents, heater outlets or to suck in outside air.
You can view the temp door as previously described by removing the Blower Module (Electronic Air) or Resistor Pod (Manual Air) on the left side of the Evaporator Case mounted on the Firewall. Have someone operate the controls and verify that it moves. If not, it's linkage is connected to the motor that controls it (Electronic Air) with a plastic clip and that clip has probably broken or the cable (Manual Air) has snapped. Access to the motor or cable is from the passenger's compartment - remove the hush panel.
If the door is working, the core is probably plugged up. When that happens, coolant flows over the top of it, but not through it. Try water from a garden hose or compressed air to flush it out. Go easy on the compressed air - normal coolant pressures are usually 15 to 17 psi. If you can't get it unplugged, you'll need to replace it.
i have the problem described and i am going to look for your solution but
i would like to ask u a question. my control unit blinks when i tried to
turn on the heater. in the owners manual it says to take out the fuses
which i did and the light did the same thing when i turned on the heater.
the manual says to take to dealer if this happens. could the blinking
light be from what you are saying? do you know what i am talking about
and have you ever encountered this? the dealer said it probally was the
control unit so i replaced it but it does the same thing.
i thank you for your time
7th Gear
Joined: May 2006
Posts: 7
Likes: 0
Hi
i have the problem described and i am going to look for your solution but
i would like to ask u a question. my control unit blinks when i tried to
turn on the heater. in the owners manual it says to take out the fuses
which i did and the light did the same thing when i turned on the heater.
the manual says to take to dealer if this happens. could the blinking
light be from what you are saying? do you know what i am talking about
and have you ever encountered this? the dealer said it probally was the
control unit so i replaced it but it does the same thing.
i thank you for your time
i have the problem described and i am going to look for your solution but
i would like to ask u a question. my control unit blinks when i tried to
turn on the heater. in the owners manual it says to take out the fuses
which i did and the light did the same thing when i turned on the heater.
the manual says to take to dealer if this happens. could the blinking
light be from what you are saying? do you know what i am talking about
and have you ever encountered this? the dealer said it probally was the
control unit so i replaced it but it does the same thing.
i thank you for your time
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Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Blinking Light means there's a trouble code stored for an HVAC system problem. Until it's fixed, nothing is going to work. Tech Tips has a procedure for accessing the Codes on the '90 and up. If you're below that Year, repost.