Heater coil?

[Sblanck]

Greetings

Wife has a 2004 Jeep Liberty
seems to have a heating issue. When vehicle hits mid way on the temp guage the air blows cold. This when the car is sitting still idling, when you start moving and get up to 30+ mph it starts blowing hot when you slow down it goes back to cold air. You can hear some sort of liquid type of sound near the dash. Heater coil going south?

Thanks

S

 

[SteelHeadz]

First things first. If the cooling system is not loosing coolant and no leaks are found, i would assume the the slushing liquid could be water in the HVAC housing that's not properly draining out, or your hearing the water passing thru the heater coil which at times when small pockets of air in the system would be very audible in the cab.. I would suggest that you try to manually calibrate the system and see if it operates normally as designed..Here's the procedures to calibrate the system.

NOTE: The manual calibration procedure can only be started within the
first ten (10) seconds after the ignition switch has been turned from the
OFF to the ON position. Make certain that the battery is fully charged prior
to performing the manual calibration procedure.
NOTE: The pause made at each end of the knob rotation (sweep) is important. If
the pause is too short (less than 0.5 seconds), or if the pause is too long (greater​

than 1.5 seconds), the manual calibration may not occur correctly.

MANUAL CALIBRATION PROCEDURE:
1. With the ignition switch in the OFF position, move the temperature select
control knob to its middle (12 o’clock) position.
2. Turn the ignition switch to the ON position (do not start the vehicle engine).
3. Within 10 seconds of turning the ignition switch from the OFF to the ON position perform
the following rotations (sweeps) of the temperature select control knob: (Fig. 1)
a. From the 12 o’clock position, rotate the temperature select control knob
counter-clockwise to the full cold position. Pause one second.
b. Rotate the control knob clockwise to the full hot position. Pause one second.
c. Rotate the control knob counter-clockwise to the full cold position. Pause one second.
d. Rotate the control knob clockwise to the full hot position. Pause one second.
e. Rotate the control knob counter-clockwise to the full cold position.
4. Turn the ignition switch to the OFF position.

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