07summitwhite

Hey guys, I have an 07 that is only 4 or 5 months old and I'M getting a funny smell coming from the A/C when I first start the truck up that lasts about 3 or 4 seconds.
Anyone know if the dealer can help me or is there something at an auto parts store I can buy to get rid of the smell?

engine2

Sounds like mold. I dont know how to get rid off it, but I do know if you run your A/C with the fan only (Snow flake button off) for the last minute or 2 before shutting your off, it will prevent the mold from forming.

07summitwhite

Thats what I thought...

Do you think if I run the fan after running the A/C for a minute or two it will help me out, or is it to late?

RonH

Here's a GM bulletin on the issue. It's for a 2002, but probably would be considered generic.





Document ID# 787457
2002 Chevrolet Tahoe - 2WD

[hr]

Odor Correction
Eliminating Air Conditioning Odor
Odors may be emitted from the air conditioning system primarily at start up in hot, humid climates. The following conditions may cause the odor:
[*]Debris is present in the HVAC module.[*]Microbial growth on the evaporator core [/ul]
When the blower motor fan is turned on, the microbial growth may release an unpleasant musty odor into the passenger compartment. To remove odors of this type, the microbial growth must be eliminated. Perform the following procedure:
Deodorize the evaporator core using Deodorizing Aerosol Kit.
Perform the following steps in order to deodorize the A/C system:
[ol]Ensure that the plenum which draws outside air into the HVAC module is clear of debris.
Disable the A/C compressor clutch operation by disconnecting the clutch coil electrical connector.
Dry the evaporator core by performing the following steps:
[ol]Start the engine.
Select the warmest temperature setting.
Select the recirculation mode.
Run the blower motor on high for 10 minutes. [/ol]
Locate an area in the air conditioning duct between the blower motor and the evaporator core downstream of the blower motor.
Drill a 3.175mm (0.125in) hole where the hole will not interfere with or damage the following components:
[*]The blower motor[*]The evaporator core[*]Any other operating part the of system [/ul]
Wear safety goggles and latex gloves in order to perform the following actions:
[ol]Select the maximum blower speed.
Insert the deodorizer extension tube into the hole to the mark on the extension tube.
Use short spray bursts and vary the direction of spray for a 2-3 minute period of time. [/ol]
Shut the engine OFF. Allow the vehicle to sit for 3-5 minutes.
Seal the 3.175mm (0.125in) hole with body sealer or RTV gasket compound.
Start the engine.
Operate the blower motor on high for 15-20 minutes to dry.
Reconnect the A/C compressor clutch coil electrical connector.
Verify proper clutch operation. [/ol]

07summitwhite

Thanks, I may have to try this.

73shark

Years ago I had a car that had a bad (mold or mildew) type smell. I turned blower on hi and sprayed Lysol in the cowl intake and that seem to work.

07tahoe

more info


https://chevroletforum.com/m_24485/tm.htm

DrakeBliss

I have a 2004 Chevy Tahoe that for the last few months when I run the rear AC I get a funny musty odor coming from the rear A/C vents. The smell was extreme when the AC was first turned on. After a while the smell would get less as the unit was run. When I developed a persistent cough that would not go away, I decided to check the rear AC. What I found was the drain tube from the rear evaporator was bent over and not draining. Mold was growing in the unit, making me sick. The drain plug is located near the AC line that goes into the evaporator. The rubber nipple was bent over and tucked into the bottom of the truck. Look for it above the exhaust pipe. I was able to pick at it with my finger and a nipple like hose end appeared. I used a wire to unplug the line. I then used a diluted bleach mixture to kill the mold that was growing on the AC condenser. I removed the panel and removed what I think might be the thermostat. This exposed a 2 inch by 4 inch hole. This allowed access to the condenser where I poured in the bleach mixture. I also used a spray bottle with bleach to spray all around in the evaporator. This cleaned it up nicely. My cough has gone away.

73shark

Welcome to the forum. Nice write-up. Not to be too nit picky but technically what you cleaned is the rear evaporator. The condensor is in front of the radiator.

smdboyz

you can try to replace the cabin air filters it worked for me.