When we first start our 2017 RDX, we get a blast of 'dirty socks' smell out of the HVAC vents. It goes away quickly, but is a bit disconcerting at first.

Has anyone had the problem, and if so, do you have any advice on curing it? There are cleaning foams that are injected into the evaporator drain line, and others that are mists that get sprayed into the air intake.

This is not an Acura problem. Searching the internet shows that just about every other car has had the problem at one time or another.

 

If you've checked the internet, you probably found comments about the drain tube being clogged. Would need to be cleared out by a shop.

 

Have you changed the cabin filter?

 

I'm able to get air up the drain tube without problem, so I think it's not plugged. I did change out the cabin air filter for a new one with carbon. Unfortunately, it is upstream from the evaporator and heater core, so homegrown odors don't pass through it.

The Acura service tech suggested getting the car good and hot, turn the heat to max and the A/C off, then turn on recirculate and let it cook for a while. He says this will heat up the evap and dry it out, killing the odor. I will give this a try.

 

You can also try a product like Frigi-Fresh
https://www.bgprod.com/catalog/clima...g-frigi-fresh/

You spray it into the intake while the A/C is on full blast. (there are videos about how to use it)
I had some and just used it on one of those roll around A/C units for the home. I have had to to use it in the past
because my wife likes to have her vehicles on recirculate all the time. This is a mistake, you must introduce fresh air most of the
time. Recirculate should only to be used to cool the vehicle quickly (something that happens automatically on our auto HVAC cars)
or going through a dusty situation, or sitting behind a stinky car.

Something else that seems counter, but is a good idea is when needing to cool down a very hot car down, open all the windows while the A/C runs
for a minute or two to allow the hot air to escape. This drives the very frugal nuts, but it works.

 

The dirty sock smell issue is as old as automotive air conditioning; the best way to prevent it is to shut off the A/C a minute or two before arriving at your destination. Using this procedure will allow the water which has condensed on the evaporator coils to dry off before the airflow stops. Once they are dry they cannot feed the bacteria which causes the smell.