Hello,

I have an 08 Grand Marquis LS. Last year I was experiencing issues with the AC stuck on Heat only. I managed to replace the blend door actuator and this fixed the issue (I was able to switch from A/C to heat and back without any trouble.)

The past 2-3 months I started to notice the A/C vents would blow a subtle small amount of heated air while driving, more noticeable on the highways. This happens despite the A/C climate control being completely off. I performed a EATC Self test and had no codes. I am not sure if this has been happening ever since installing the new Blend door and just didn't notice or if it started within the past 3 months.

Again, I have no issues adjusting the A/C or heater to the desired temperature.

Any help/ideas on what the problem could be is appreciated. I am wondering if the blend door isn't closing entirely; I had also wondered if there needed to be some type of recalibration of the blend door

Jose