hello i have 99 ford contour 2.0 and it dies on me evertime it's idling or when i'm stopped and my foot on the break while in gear i had the codes checked and they said that the fuel was too lean/rich can the oxygen sensors cause this issue and 1 more thing when it goes to stall i quickly press the gas and it stays running but i smell some sorta weird smell from either the engine or the exhaust PLEASE HELP it's getting worse

 

Can you supply the codes you received?

 

It is probably a vacuum leak. On our '00 contour, same engine, the PCV hose was going bad. I replaced it before it had a hole.
Check everything around the intake plenum for vacuum leaks.
Clean the MAF sensor with MAF sensor cleaner.
If you have not done that recently: change spark plugs and wires, inspect the coil pack and replace it if needed. Replace the air filter if it is dirty.

Is the strange smell a bit like rotten eggs? Is it more like fuel?

The strangest smells our Contour had were related to animals. A mouse made a nest in the engine compartment and distributed some maple seeds. Some of them I found on the exhaust manifold, roasted!
Possibly the same mouse had babies under the rear bench. They died there and that smell was worse than the skunk we hit one day.

Febreeze to the rescue!