Solution to resolve your small evap leak, gas smell, P0442 on 4runners
As the 3rd gen 4runners are aging, more vehicles will encounter these problems. I spent many hours to get to the bottom of this issue.
Solution to small evap leak, P0442, fuel smell at the rear driver side of the vehicle:
1) charcoal canister (can be confirmed with a smoke test). Part cost = $300 to $400.
2) overfill or also called check valve on top of the fuel tank is leaking (small leak cannot be detected by the smoke machine, typically about 0.040 or less size leak). Part cost under $100.
3) filler neck can be rusted & leak if you're in heavily snow regions. Part cost, I think $200.
Some mentioned replacing the gas cap, but I haven't seen this to be an issue unless it's been dropped or the seal gasket is cracked.
If check engine light (CEL or MIL) is ON, your VSC & Traction will also be ON or those functions are disabled. Vehicle drives fine until you need an annual inspection. You'll also experience slipping and sliding in wet or snow surface until you clear the CEL.