Bad Smell problem - gas tank vapor recovery system
Hoping for some input on this problem.
For several years now, there is a hint of a sweet sickly chemical smell at times inside and outside the truck.
Thought it was the AC freon oil leaking but I haven't had to recharge it.
Thought it was the radiator or heater core or other part of the cooling system leaking but I don't think it smells quite like coolant and I've pressure tested the system and cap several times and no leakage found.
The smell was strong the other day with half a tank of gas, and I believe my nose may have found the source. It seems the smell is coming from the two square canisters that are like the charcoal fuel tank system vapor recovery system that are under the hood to the driver's side of the radiator.
Why would such a strong chemical smell be coming from there and what is the remedy?
I replaced the gas tank rubber hose filler neck about 4 years ago which stopped the gasoline smell leaking in that area and the gas cap is pressurized when I remove it for refilling.
Any input would be appreciated.