2019 Tahoe Rear A/C Smell

[smitty_10]

As the title says, we have a foul smell coming from the rear A/C in our 2019 Tahoe.
Found a couple of Youtube video showing rear A/C repair and noticed that the unit is located above the right rear wheel. There are some vents on the interior at this location, but it doesn't have a strong airflow. I tried to run the A/C on max and spray some Lysol here and it helped some. From images of the A/C unit I can't tell where the air intake is. Has anybody dealt with this problem before? Trying to take care of this without removing the interior panels.

 

[OR VietVet]

Welcome to the forum.

Lots of threads here about a/c smells. I personally have never experienced the problem. You can get a spray at the parts store to address this concern and follow directions. The smell typically is caused by a build up of mold from an a/c system not draining properly from the evaporator sweat. May need to dismantle the covers to gain access to address the drain or can get under and look. With a/c on and running, there should be a dripping of water from the drain to the ground. Check out a few you tube videos about this concern.

 

[BlaineBug]

The rear vent there at the tailgate is not a vent for the HVAC. The rear HVAC either blows through the 4 ceiling vents or the lower fender vent on the passenger side just behind the passenger rear door. I assume the rear HVAC uses the same cabin filter as the front HVAC. Have you replaced it recently? I'd suggest replacing it annually.

 

[BlaineBug]

The rear vent there at the tailgate is not a vent for the HVAC. The rear HVAC either blows through the 4 ceiling vents or the lower fender vent on the passenger side just behind the passenger rear door. I assume the rear HVAC uses the same cabin filter as the front HVAC. Have you replaced it recently? I'd suggest replacing it annually.

Does that panel on the passenger side remove like the driver side panel does?

 

[B-train]

You need to look behind the rear wheel well on the passenger side for the drain tube. There's a flat floor pan area where all the lines go through, your drain is near them. If the drain is plugged, you will have all sorts of musty smells. When you find the drain, run a zip tie or something else non metallic up there and see if it's free. You can also back blow them with compressed air to see if they are blocked up.

I'd pull the interior panel off and do an inspection. Spraying lysol through the air intake isn't a solution. There is no outside air inlet for those from what I've seen. They pull cabin air and move it around to the ceiling or floor vents. All air comes through main cabin filter.

 

[BlaineBug]

You need to look behind the rear wheel well on the passenger side for the drain tube. There's a flat floor pan area where all the lines go through, your drain is near them. If the drain is plugged, you will have all sorts of musty smells. When you find the drain, run a zip tie or something else non metallic up there and see if it's free. You can also back blow them with compressed air to see if they are blocked up.

I'd pull the interior panel off and do an inspection. Spraying lysol through the air intake isn't a solution. There is no outside air inlet for those from what I've seen. They pull cabin air and move it around to the ceiling or floor vents. All air comes through main cabin filter.

I've also been told Lysol is flammable. Not the greatest for spraying around electric blower motors and/or fan resistors.