We would need to Know WHICH Saturn and make and size of tire.
The pressure is the same whether they are new or old tires.
Even though all four tires have the correct tire pressure, the light will stay on if the pressure in the spare tire is incorrect. This is because of a sensor in the tires.
If air is escaping from your tires then you have a leak. Repair the leak and no more air will escape. This is not to say you never have to check the air pressure. Tires are made from a porous material and as such will loose a very small amount of air even under the best of circumstances. Check the pressure on a regular basis.
The correct amount of air pressure for your car tires can be found in operator manual or even possibly on tire. Do not over inflate to prevent blow-outs on road.
The tires go flat. The tires lose air even if they don't have any defects or holes, the air goes right through the rubber by osmosis. For applications where tire pressure is critical they use nitrogen to inflate them. One of the amazing things about air in tires is that different gasses depart the tires with different speeds. Probably a good science project in this.
just look in the door jam of the driver door. will tell you tire size and correct air pressure for the vehicle.
Owner's manuals usually recommend to check the tires' air pressure weekly.
air pressure
No -- Keep the same recommended air pressure in your tires at all times, but check and add air when the tires are cool and have not been running. Use a tire pressure gauge.
The first and most important aspect of this is that an owner and user of a farm tractor should be constantly measuring the air pressure. If the pressure is staying below 15 PSI even after adding air, it is time to change the tires.
A tire pressure gauge.
Low pressure.
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