MichaelJr19

AC Odor Issue After Warm Restart – 2018 Chevy Colorado I’m experiencing a recurring issue with my Chevy Colorado where a chemical-like odor comes from the AC only after a warm restart. This has been ongoing since my first summer with the truck. I previously visited both a GM dealership and an independent mechanic, but neither was able to identify the root cause. The dealer recommended enabling the after-blow feature, which has been done, along with any other basic HVAC adjustments they suggested. A few details: The odor does not occur during cold starts, even after hours of continuous AC use. There’s no noticeable water buildup, and I don’t go through car washes. The smell appears only after the vehicle has been turned off briefly—typically after a stop for gas or picking someone up (5–10 minutes). Upon restarting and turning the AC back on, a noticeable chemical smell (not musty) comes from the vents. If I leave the AC off and just run the blower for several minutes (even while the cabin gets hot in the summer), the smell usually goes away and won’t return when the AC is turned back on, except if I have another short stop. I’d appreciate any insights or next steps that could help identify and fully resolve the issue. Thank you.