The symptoms: Kind of a syrup-type smell inside the cabin when the heat is on, or when the heat isn't on, you can smell it under the hood.

So I know an egg smell usually indicates a bad cat but this smell only comes through when the heat is on so I'm thinking it's either something really dirty in the heater core or it's bad all together. The heat still works great, and no overheating problems at all, but if you know the history of my truck (~8-9 radiators) a heater core problem doesn't sound all that surprising.

Anyone know for sure what it could be, or do you agree that it's heater core? anyone else ever experienced it?

Thanks, i love the Yotatech knowledge base!!