Foul smell from a/c at start up

[gtptyler]

There is a foul smell coming from my vents immediately after start up on my 2014, almost smells like manure. It started shortly after it started getting warmer outside this spring. Had it checked on during my first oil change and they came up with a reprogram to leave a fan of some sort on for a few seconds longer after shutting the truck off to dry something off in the system. Well of course that hasn't made any difference. Also some start ups it smells stronger, I haven't found any correlation to how long it has sat.

 

Anyone else have this issue?

[j13smiley]

Is it parked outside? My '10 had to be parked downhill on the driveway to keep from smelling.

 

I've not noticed this issue with my '14 though.

[00Silverado4x4]

You will have a drain for the evaporator in the engine bay area. It could be getting plugged up. If water gets trapped in there it will cause stagnant water to get real nasty real quick. Find the drain and make sure it's open. I had this happen on my truck a few years ago after sitting for a few months during the summer months of Georgia. If you're going to have it sitting for a while it's a good idea to turn off the AC prior to shutting off the engine to ensure the evaporator has drained and dried out.

[gtptyler]

Its driven daily but garaged at night. Will double check the evap drain tomorrow

[keakar]

 

Its driven daily but garaged at night. Will double check the evap drain tomorrow

 

use qa shop vac to suck it clear

 

sometimes when the boxes are squished together the putty blocks the drain ports then it clogs easy so if you can reach it you can try sliding a thick string like weed whacker string in there to be sure its clear and not obstructed.

 

if its obstructed use a coat hanger or something stiff but that you can shape to the right angle to try to push the body putty out of the opening

[pm26]

We have pesky small birds here in

Florida that like to build nests inside cars and truck engine compartments. One built a nest on top of the cabin filter of my Sonic and when I turned the A/C on the car stank like there was a dead rat in the ducts. How that bird got in there I have no idea. they look for the most hidden places possible and sometime they will peck at the underhood insulation to use it as nest material. I removed a complete stinky nest built on top of the filter and the filter had to be changed too as it stank horribly.