How do i replace a heater control valve on a 2001 sierra 1500 pick up

check antifreeze level add if low, and check intake heat control valve on ps side of intake if its locked shut it can be removed and a water pipe nipple put in place of it and the heater hose reconnected..if the water pump is good, it should give heat this valve should be on the intake with a heater hose connected to it..and its vacuum operated but will jam shut with age and cold weather..good luck..

thermostat stuck or heater control valve bad..you may have air in the system too

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This may be your problem. The blend door may not be opening.

Check coolant level. Check for heat at the heater hose going from water pump to heater core at firewall. Check to see that cable is moving coolant control valve from the closed to open position. Low mileage so it shouldn't be plugged heater core.

are heater inlet outlet mix valves standard for all dodge heater cores. I have 2001 dodge cummings blows warm air not hot when gauge is 195 degrees would there be a mix valve under the dash because it is not inline outside the wall

Check the water control valve behind the engine close to the firewall. This valve opens and closes to allow hot coolant to enter the heater core. It is usually connected to the heater controls with a cable. When you adjust the heater control for heat, a cable activated lever on the valve should move and allow coolant to move through the valve. The cable from the heater control can come loose from the lever, or the valve itself can become corroded and hard to move.

Check in the one heater hose will be a control valve. Check the operation of the valve(this is the heater control valve). If the lever on it appears to be moving. Take the valve out and manually check that the valve is opening and closing the whole way. If not replace the valve and recheck. If it is the heater core may be clogged not allowing the hot coolant to flow thru so you can get heat.

THE HEATER RESISTOR IS LOCATED UNDER THE HOOD ON THE RIGHT SIDE OF ENGINE COMPARTMENT..2 SCREWS AND A 4 WIRE CONNECTOR..VERY CLOSE TO WHERE AIR INTAKE HOSE RUNS TO AIR CLEANER HOUSING..FAIRLY INEXPENSIVE TO REPLACE..PICK UP A NEW ONE AND YOU'LL SEE WHAT YOUR LOOKING FOR

How hot this gets is often regulated by the engines ability to properly heat up. This is controlled by the engine thermostat. Alot of times, people who have an overheating problem simply remove the thermostate without replacing it. This does not allow the engine to heat up properly (it actually is running too cold) thus the water coolant does not heat us. result, barely warm air through cabin heater.

make sure antifreeze is full. run engine 10 min. verify engine is around 195 degrees. if not, try replacing thermostat. if it is running at 195, then maybe heater core problem or heater control not functioning properly