BobG999999
New Member
I've been checking for a while, haven't found anything that works.
1997 Tahoe, 5.7, 4x4, 4 door.
When you change the temperature on the dash, you feel a slight increase in temperature, not nearly what should happen. Checked heater hoses, both hoses, both before and after the valve, are all 180 - 200 degrees with infrared thermometer. Ran water through heater core, flowed perfectly.
Heater temp door actuator is working. Can see it moving between the two marks on the case. Took it off (what a pain) and can move the blend door with a screwdriver both directions. Can hear it "flap" into place when moving it to the colder setting. Put the actuator back on and warmed up the truck. Vents are cold, until I move the temperature knob, then it warms slightly. Put a 195 degree thermostat in, drove for a bit, maybe a slight improvement, but I couldn't really tell.
So, coolant is flowing through the heater core, hoses are hot, blend door appears to be working. I can't think of anything else.
Any thoughts appreciated.
1997 Tahoe, 5.7, 4x4, 4 door.
When you change the temperature on the dash, you feel a slight increase in temperature, not nearly what should happen. Checked heater hoses, both hoses, both before and after the valve, are all 180 - 200 degrees with infrared thermometer. Ran water through heater core, flowed perfectly.
Heater temp door actuator is working. Can see it moving between the two marks on the case. Took it off (what a pain) and can move the blend door with a screwdriver both directions. Can hear it "flap" into place when moving it to the colder setting. Put the actuator back on and warmed up the truck. Vents are cold, until I move the temperature knob, then it warms slightly. Put a 195 degree thermostat in, drove for a bit, maybe a slight improvement, but I couldn't really tell.
So, coolant is flowing through the heater core, hoses are hot, blend door appears to be working. I can't think of anything else.
Any thoughts appreciated.
