1) A hole or crack in the engine block 2) leak in any oil passageways or hoses. 3) Missing oil pan plug. It would be best to get underneath your car and look for oil leaks. If ALL your oil is gone then you should have no problem identifying the leak. Pour a little oil in the engine oil filler hole and see where it leaks back out. DO Not drive without oil!!!! you'll ruin your engine.
a small evap leak would not cause your car to jerk.
I would not expect a valve cover leak to cause a car to stall. A valve cover leak can fill the spark plug area with oil which can cause rough running.
No.
No...
YES, That would be called a vacuum leak.
Leaking valve cover gaskets would leak onto the exhaust pipes under the hood of the car.
An oil leak is always going to be out of the engine as the engine contains oil and the car does not. I think you are saying you are loosing oil with no apparent leak. If that is the case the engine is burning oil and that is why you see no leaks.
you have a leak in your heater core which is attached to your radiator and heats the air inside your car interior
Yes but it would have to be pretty large and lean codes would precede it illuminating CEL/MIL
Yes.
A vacuum leak can cause that.
Any fuel spill,storage or leak can cause fuel odor inside the car.