New Truck - Weird Smell Coming From Hvac Vents

[davefr]

I bought a brand new '06 Sierra 2500HD w/8.1 V8 in late Jan. The HVAC vents emit a somewhat strange smell similar to maple syrup. It always comes when I first get in the truck but diminishes after about 10 minutes of driving. It will re-appear next time I drive the truck.

 

It does not smell like the coolant system and it doesn't really smell musty. (nor is it the characteristic new car smell)

 

I've read similar threads but no-one has posted what the root cause/solution is. Is it mold in the evaporator? Should I take it to the dealer? I hate to go thru dealer hell if it's something easily fixed by myself.

 

What are the solutions?

[lord-dogbert]

Heater core, mine did the same thing, though later in my trucks life.

 

Stealer got $145 to clean "mold" off of the evaporator. Things smelt great for a few weeks but the maple syrup smell came back. The heater core just blew a few weeks ago hauling up Sherwin grade on I395. Blew anti-freeze steam all over the cab. Bypassed the core at Mamoth lakes and carried on my vacation.

 

Stealer replaced the heater core under GMPP (free after I raised enough hell to chase customers away). I looked at the core, it was disgusting and evident that there had been some sort of leak there for some time.

[vmikels]

I have a similar problem from a 2007 Envoy but smells more like an antiseptic or dentist or doctors office. Mine does it more often than when I first start it up. My local dealer said they couldn’t get the ac to do it at the time it was at the shop. Hope you get your problem found.