High Idle Led to Gas Smell?

I have a 95 4runner that I bought in Seattle and drove through 13 states then back up the Alcan, to Anchorage. It limped into anchorage, on the final stretch it started smoking white smoke. We got the valve cover gaskets replaced, all the money we had. There was still a high idle ~ around 1800 RPM. After a few months of this a raw gas smell started appearing after driving it and getting out of the drivers side area.

Then today sitting at a traffic light, it had a very sudden lug, dropped to 800 RPM seemed like it was going to stall, then climbed back to 1800 RPM.

Seems complicated.

Any thoughts on what systems to check into?

 

based just on the white smoke and replaced valve cover,
PCV valve.
stick a vacuum gauge on it. 10 bucks at harbor freight,.
its the best trouble shooting tool.

 

gas smell = charcoal canister needs checking and the bottom filter cleaned.

 

bottom filter thats on the the charcoal canister.