Heater not working properly on driver's side only

DAKEELER

MEMBER
2011 BUICK REGAL
4 CYL
2WD
AUTOMATIC
93,000 MILES

My sister owns the car listed above. Since March 2021 after having a coolant flush done at Tuffy in Shelby Twp, her heat on the driver's side only has not been blowing out warm air if the temperatures outside are in single digits up to 20 degrees. It blows good air, just not warm.

Took it back to Tuffy. They replaced the left side blend door motor, replaced fuel pump (because gas leaking into the oil) and replaced HVAC control module. Still wasn't working.

Took it to Vyletel Buick and they reprogrammed a couple of things. Went to pick it up on a Saturday. I never left the parking lot as it was only 10 degrees outside. No warm air on the driver's side after running it until it started warm air on passenger side. Left it there after a service advisor tested the temperature. Drivers' side 20 degrees, passenger side 55 degrees. They don't have any service technicians to work on it on Saturdays.

Thursday, they did a coolant flush and back flush thinking something was plugged. Why nothing was done before Thursday I don't know. The service advisor said if this doesn't work, they will have to redo everything Tuffy did. The warm air wasn't blowing before they did any of the replacing, why would replacing what they did help?
Temperatures weren't cold enough until this morning. Guess what? No warm air on the driver's side. I came back from church and the temperature outside was 19 degrees and there was warm air blowing on the driver's side.
This is so frustrating to say the least. She has paid almost $1,500.00 and is still not working.

If anyone has any ideas or suggestions, please let me know. She can't keep putting money into it.

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,885 POSTS

Hi,

If the passenger side is working properly, that tells me the heater core is getting hot. From there, the temperature that enters the vehicle is controlled by the blend air door. You indicated they replaced the blend door actuator. Either it wasn't installed correctly, it's loose, or the actuator is bad. Do you know if they used an OEM part?

Let me know. In the interim, here is what I suggest: The actuator is really easy to replace. It is held into the heater box by two screws. I would suggest removing it and then reconnecting it. Adjust the air temp to the max in both directions to see if the motor responds. If it does, then plate some resistance on it to see if there is a clicking that seems to prevent it from moving.

Here is a link that shows in general how one is replaced. Use this to help guide you to the removal and reinstallation of the actuator. Also, read through the link. It explains how it works and what commonly goes bad.

https://www.2carpros.com/articles/replace-blend-door-motor

If you look below, I provided the directions specific to your vehicle.

Let me know what you find or if you have other questions.

Take care,

Joe

See pics below.

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