The largest online repair guide library for every car

About us
Contact support
FAQ
Sign up
Sign in

2016 MKZ AC Not Cooling, Blowing Hot Air Only

0

Mike T. · rep 0 · May 25, 4:27 AM · 1 replies · solved · Question

Vehicle: 2016 Lincoln MKZ 2.0L

Hey everyone,

My 2016 Lincoln MKZ, with the 2.0L engine and about 90,000 miles, has developed an AC problem. It suddenly stopped blowing cold air a few days ago. Now, no matter what setting I put it on, it only blows hot air, even with the temperature set to 'LO'.

The fan works fine, and I can hear the compressor engage sometimes, but it doesn't seem to be making any difference. I haven't seen any warning lights or gotten any specific OBD codes related to the AC system. I checked the refrigerant pressure with a cheap gauge from an auto parts store, and it seemed to be in the green, but I'm not sure how accurate that is.

Could this be a blend door issue, or something more serious with the AC compressor itself? Any common issues with the MKZ's AC system I should be aware of?

✓ Accepted solution

ClearTheCode Admin

ClearTheCode Team · rep 0 · May 25, 4:27 AM

0

ClearTheCode admin answer:

It's frustrating when your AC stops working, especially in a Lincoln MKZ designed for comfort. While you haven't seen any codes, this is a common diagnostic problem. Here's a breakdown of potential causes for your 2016 MKZ blowing hot air:

  1. Refrigerant Leak:

    • Cause: Even if your gauge showed 'green,' a slow leak might have depleted enough refrigerant to prevent proper cooling. The system needs a specific amount of refrigerant to operate efficiently. If the pressure is too low, the compressor may not engage fully or at all to protect itself.
    • Action: A professional AC service includes a vacuum test and recharge to the precise factory specification. They can also add dye to detect leaks.

  2. AC Compressor Clutch/Compressor Failure:

    • Cause: You mentioned hearing the compressor engage 'sometimes.' If the clutch isn't consistently engaging, or if the compressor itself is failing internally, it won't be able to circulate refrigerant.
    • Action: Visually inspect the front of the compressor when the AC is on maximum. The inner hub should spin with the outer pulley. If it's not, the clutch or compressor could be faulty.

  3. Blend Door Actuator:

    • Cause: This is a very common issue across many Ford/Lincoln vehicles. The blend door actuator is a small electric motor that controls a flap inside the HVAC system, directing air through either the heater core or the evaporator core (for cold air). If it fails or gets stuck, it can prevent cold air from entering the cabin.
    • Action: You might hear clicking or whirring sounds from behind the dash when changing temperature settings. Sometimes, a diagnostic scan tool can pull codes related to HVAC actuators, even if no CEL is present.

  4. AC Pressure Sensor/Switch:

    • Cause: This sensor monitors refrigerant pressure. If it fails, it can send incorrect readings to the PCM, preventing the compressor from engaging even if the pressure is fine.
    • Action: This would require diagnostic testing with a scan tool to monitor sensor readings.

  5. Clogged Cabin Air Filter:

    • Cause: While usually not the primary cause of no cold air, a severely clogged cabin air filter can restrict airflow, making the AC feel very weak.
    • Action: Check and replace your cabin air filter if it's dirty.

When to See a Shop: Given that you're getting only hot air, it's best to take your MKZ to a qualified technician who specializes in AC systems. They can perform a comprehensive diagnostic, including:

  • Accurate refrigerant pressure and volume checks.
  • Testing the compressor and clutch operation.
  • Scanning for HVAC-specific fault codes.
  • Diagnosing blend door actuator function.

Attempting to simply 'recharge' the system without finding a leak or diagnosing the root cause will likely lead to the problem recurring quickly.

Menu

Help & account