it should be somewhere from 35 to 40 psi most likely. the best way to find out is to look on your driver door jam for the sticker that shows what the pressures should be at.
You should consult your owners manual or look in the car's door jambs for the inflating sticker. It will tell you how much cold tire pressure for each available tire.
The tire pressure for a Hyundai Elantra tire is recommended to be around 32 PSI. If the tire requires greater or lesser pressure it will be written on the tire.
A typical tire pressure is in the range of 30-40 psi. However, you should check the sidewalls of your tires, as these should have the required pressure printed on them.
