What should I do in the case of a gas leak at home?

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YOU HAVE TO TAKE [ EXTRA PRECAUTION ] WITH ENGINE OFF CHECK THE GAS LINES THAT LEADS TO THE JETS SOME TIMES THE HOSES THAT ARE CONNECTED TO THE JETS KIND SPLIT AND THAT CAN COUSE A SLOW LEAK,
EXAMPLE--WHEN YOU DRIVE THE CAR YOU WON'T SMELL THE GAS CUASE IT EVAPORATES SO IS NOT THERE,THE ONLY TIME YOU CAN SMELL THE GAS IS WHEN YOU GO HOME AND PARK AND WHAT EVER PRESSURE IS IN THE GAS LINE THE GAS WILL ESCAPE OVER NIGHT VERY SLOW,YOU CAN TRY THIS-
WHEN YOU GET HOME LET THE CAR SET FOR 1 HOURS THEN CHECK JETS FOR WET SPOTS.
TAKE CARE OF PROBLEM SOON AS POSIBLE
GOOD LUCK.

Metro, which engine G10 or G16?

you have a very dangerous car, first do not park near your home'
use the street curb. gas can and will catch fire if it leaks.
and 10x that near spark plugs (this case)
you have a gross failure in the injection system.
get it fixed fast.
my wild guess, (blind cant see leak) is the Injector 0rings have failed
at the fuel rail, this is too common on very old cars)

fuel line has probably not been tightened properly

do not drive car, do not park near home or in any garage.
keep in in the drive way.......
find the source. (look and sniff) or get help'
gas cap fell off
OMG, injectors leaking or fuel rail, or fuel filter?
OMG gas lines (under up to 60PSI presssure) leaking?
EVAP system , breached?

Make sure you don't overfill when at the gas pump.

I wish I could be sure and say its the evap hose or the charcle canister that collect gas fume a sends it to the intake for fuel,but in your case you just bought it, be safe take it to a shop let them inspect the vehicle for your concern

If there was a leak you need to find the point of leak first so as to recitfy and then the gas must be refilled. In some cases it cannot be the joints or the hose but can happen in the cooling coils or the condenser. If so you will need to release gas and then use a pressure system to check for leak - such equipments- comrpessor- is need to check the leaks at high pressure or else the gas filling will be a wasteful operation.

The issue you describe is serious and dangerous... have it properly diagnosed by a competent/certified Hyundai Technician!

Over an extended period of time gas will evaporate in a carburator. It's possible that presure is leaking off in your fuel pump as well. A weak pump will have trouble maintaining pressure over a period of time and will have trouble building pressure back up. Starting the engine on a regular basis and letting it run for a few minutes will cure the problem and help keep the engine seals from drying out and leaking. Converting to an electric fuel pump will also make it easier to start after sitting for a period of time.
Any generic LOW PRESSURE electric pump will work. It only needs to put out between 7 and 9 or 10 pounds pressure. Unhook the fuel lines from your mechanical pump and hook to the electric. The li ne from the tank goes on the inlet end. The electric pump usually ground through the case so it needs contact with bare metal or a wire running from the case to bare metal. Run the power wire to a powered wire in the engine compartment that powers on and off with the key or to an accessory fuse in the fuse box. It should run through a 20A fuse.
Hope this helps.