Any car can start on fire any time. If you tend to smell gas when your around your car it would be in your best interest to have it inspected by a mechanic as soon as possible.
There are many reasons why your car might vibrate while it is idling. It could be running too hard for example.
your throttle body could be sticking i'd start by cleaning that
it could be your timing is off
There can be many reasons why a car surges while idling. Some of these reasons are the computer could be dying, or the fuel injector are giving the engine too much gas.
More info will be needed to properly answer your question. There could be a multitude of reasons. Does your vehicle start at all? Does it stall while driving or idling?
the engine will turn over but sometimes wont start. it also sometimes dies while its idling. whats going on
The oil could be old and needing change. The oil filter could be getting stopped up, or the screen on the oil pump could be clogged. An oil change and new filter is the first place to start.
It could stall if you use the rear brake while going downhill. Is this the case?
prob a vacume leak
probably the fuel pump
unit could be low of refridgent,or valve for heater not closing complety There can be other problems, but these twowould be the ones i would start with.
Effectively all the fuel that it burns while idling. You are getting 0 miles per gallon while idling.