heater issues
More Turbo
Joined: Dec 2002
Posts: 664
Likes: 129
From: Columbia, MD
Details?
You can turn the **** from hot to cold, but it stays cold? Or can't turn the ****?
If you can't turn the ****, then something in the mechanism is jammed. If the **** turns too easily, then something in the cable mechanism has broken or fallen off.
If the **** feels "about right", then either
a) hot coolant isn't getting into the heater core, or
b) something has the blend door jammed partially open in the "cold" position.
Check your coolant temperature... if the truck isn't warming up, then thermostat problem is likely. If coolant warms up "about right", check the temperature of both heater hoses after the engine is good and warm. Both hoses should be as warm a main radiator hose. If one or both are cold, suspect a blockage, possibly in the core. With the engine cold, it's pretty easy to pull both hoses and flush the core, and see if water comes out the other fitting.
If the truck is warming up and both heater hoses are good and warm, suspect that the temperature blend door is jammed at least partially open. Things can fall down the vents in the dash and lodge in the blend door, and prevent it from closing to "warm". The temperature control **** can feel normal, but the door won't close, and you're cold.
On mine, the culprit was a pen between the door and its seat. I replaced thermostat, pulled the hoses and flushed the core, and still had no heat.
I recollect pulling the glove box and at least one other access panel or hatch behind it, blindly feeling around in the duct for a while, and not guessing until I worked the temperature **** and heard something rattle. Groped some more, and caught the culprit. A good little pen light and an inspection mirror should be a big help, but it's still a PITA.
If you can't turn the ****, then something in the mechanism is jammed. If the **** turns too easily, then something in the cable mechanism has broken or fallen off.
If the **** feels "about right", then either
a) hot coolant isn't getting into the heater core, or
b) something has the blend door jammed partially open in the "cold" position.
Check your coolant temperature... if the truck isn't warming up, then thermostat problem is likely. If coolant warms up "about right", check the temperature of both heater hoses after the engine is good and warm. Both hoses should be as warm a main radiator hose. If one or both are cold, suspect a blockage, possibly in the core. With the engine cold, it's pretty easy to pull both hoses and flush the core, and see if water comes out the other fitting.
If the truck is warming up and both heater hoses are good and warm, suspect that the temperature blend door is jammed at least partially open. Things can fall down the vents in the dash and lodge in the blend door, and prevent it from closing to "warm". The temperature control **** can feel normal, but the door won't close, and you're cold.
On mine, the culprit was a pen between the door and its seat. I replaced thermostat, pulled the hoses and flushed the core, and still had no heat.
I recollect pulling the glove box and at least one other access panel or hatch behind it, blindly feeling around in the duct for a while, and not guessing until I worked the temperature **** and heard something rattle. Groped some more, and caught the culprit. A good little pen light and an inspection mirror should be a big help, but it's still a PITA.
