No heat - HELP
Thread Starter
Racer
Joined: Jan 2003
Posts: 321
Likes: 0
From: Birmingham AL
No heat - HELP
1992 LT1 Coupe. Only had it a couple of months. Hasn't really been cold here but now it is. Noticed that heat didn't work all that well. Periodically could feel warm air coming out the vents.
I flushed my system today using the procedure in the tech section. As a test, I removed the thermostat and refilled the system with water. I purchased a 160 Deg thermostat and will install. I cranked the car and vented all of the air out of the system. Topped off with water.
Temperature came up nicely and stabilized about 210 Deg F. Both upper and lower radiator hoses were hot. However, the two hoses going to the heater core were not. The hose coming off right below the thermosat was barely warm. The other hose which T's into the upper radiator hose was cool. Appears no warm water is going through the heater core. The air coming out of the vents never got warm even though I set the heater temp on 90 Deg.
Any help on what I need to check.
Thank you in advance .... Jim
I flushed my system today using the procedure in the tech section. As a test, I removed the thermostat and refilled the system with water. I purchased a 160 Deg thermostat and will install. I cranked the car and vented all of the air out of the system. Topped off with water.
Temperature came up nicely and stabilized about 210 Deg F. Both upper and lower radiator hoses were hot. However, the two hoses going to the heater core were not. The hose coming off right below the thermosat was barely warm. The other hose which T's into the upper radiator hose was cool. Appears no warm water is going through the heater core. The air coming out of the vents never got warm even though I set the heater temp on 90 Deg.
Any help on what I need to check.
Thank you in advance .... Jim
Melting Slicks
Joined: May 2001
Posts: 2,143
Likes: 7
From: San Diego CA
Re: No heat - HELP (jimswhite92)
Could be a plugged restrictor. The restrictor is a small plastic connector in the hose from the heater to the water pump. It has a hole in the center that is about 1/8"-3/16". If you remove the restrictor be sure to mark which way it came out, the hole is supposed to be directional!
Next maybe a plugged heater core. You'll have to pull the expansion tank to get to the second hose from the heater core. It's a real short "J" hose into the bottom of the expansion tank. I just used a garden hose on the heater hose to flush it out. Becareful, household water pressure can be a lot more than the heater core is built to withstand.
There is another possiblity there are some bad resistors on the electronic control board. I have a link somewhere. I'll see if I can dig it up and post it later.
Next maybe a plugged heater core. You'll have to pull the expansion tank to get to the second hose from the heater core. It's a real short "J" hose into the bottom of the expansion tank. I just used a garden hose on the heater hose to flush it out. Becareful, household water pressure can be a lot more than the heater core is built to withstand.
There is another possiblity there are some bad resistors on the electronic control board. I have a link somewhere. I'll see if I can dig it up and post it later.
Thread Starter
Racer
Joined: Jan 2003
Posts: 321
Likes: 0
From: Birmingham AL
Re: No heat - HELP (John Row)
John, thx for the response. Is the restrictor plug nearer the core or the water pump??? I am assuming the water is controlled by a switch somewhere in the expansion tank. I see a couple of wires on the bottom??? :confused: :confused:
Thread Starter
Racer
Joined: Jan 2003
Posts: 321
Likes: 0
From: Birmingham AL
Re: No heat - HELP (John Row)
Tried to locate the restrictor plug. Could not find. The hose from the water pump goes directly to the expansion tank. From the expansion tank, a "J" shaped hose goes to the heater core. Another hose goes from the other end of the heater core and "T's" into the upper radiator hose. There is a connection in this hose. It looks like where someone bypassed the throttle body.
One thing to note, when I accelerate, I notice some heat coming out of the vents. The air goes back to cool when I am at idle.
I am going to flush out the heater core next. If there are any other suggestions please let me know. I welcome and appreciate all help.
Jim
One thing to note, when I accelerate, I notice some heat coming out of the vents. The air goes back to cool when I am at idle.
I am going to flush out the heater core next. If there are any other suggestions please let me know. I welcome and appreciate all help.
Jim
