How to pump air in car tires

How to Check Vehicle Tire Pressure and Inflate Tires

We all know that routine maintenance is important for everything from our computers to our cars. But sometimes, we fall short. One of the most neglected routine car maintenance tasks is to check tire pressures and inflate them as necessary. That’s why newer cars have tire pressure warning lights, or tire pressure monitoring systems (TPMS), that let you know when you have under- or over-inflated tires (when any tire is 25% underinflated).

Older vehicles don’t have this useful warning light. So, don’t wait for a rupture to check or change a tire. Use this guide to learn how to check the pressure (PSI) of your vehicle tires and how to inflate them to the proper air level.

Why should you check your tire pressure?

The number one reason why you should periodically check your tire pressure is SAFETY, but there are monetary and handling reasons as well:

  • Longer lasting tires
  • Improved handling and control
  • Reduced risk of accidents and blow outs
  • Better fuel economy
  • Reduced carbon footprint

Proper tire pressure (as recommended by the manufacturer) is needed to drive safely and efficiently. According to a 2009 report by the National Highway Traffic Safety Administration:

“…about 28% of light vehicles on our Nation’s roadways run with at least one underinflated tire. Only a few psi difference from vehicle manufacturer’s recommended tire inflation pressure can affect a vehicle’s handling and stopping distance. Poor tire maintenance can increase incidences of blowouts and tread separations. Similarly, underinflation negatively affects fuel economy.”

When your tires are underinflated, the tires get fatter, increasing their surface area. This causes high heat generation and extra resistance that could result in higher fuel costs, blown out tires, tire wear, and loss of control.

If you feel like you’re spending too much at the gas pump, it might be your tires. According to the US Department of Energy:

“You can improve your gas mileage by 0.6% on average—up to 3% in some cases—by keeping your tires inflated to the proper pressure. Under-inflated tires can lower gas mileage by about 0.2% for every 1 psi drop in the average pressure of all tires.”

In addition to safety and fiscal concerns, keeping your tires properly inflated will also reduce your impact on the environment. When your tires are properly inflated, you’ll pay less for gas, replace your tires less often, and improve your handling and stopping distance. You’ll also feel better knowing that you are emitting less carbon dioxide and other harmful substances into the atmosphere.

What is the right PSI level?

PSI stands for pounds per square inch. The recommended PSI for your vehicle’s tires is determined by the vehicle’s manufacturer and the recommended tire size.

One big question that we get is whether you should follow the recommended PSI level on the tire itself or the recommended PSI level printed in your owner’s manual or on the placard inside of door edge, glove box door, or fuel door.

Do NOT use the max PSI that is printed on the tire sidewall. This is not the recommended PSI level. The pressure amount on the tire is normally the maximum allowed pressure. The correct PSI level is almost always less than what you see printed on the side of the tire. Over-inflation can lead to poor handling and comfort, overheating and blow outs. Over 40 PSI is a dangerous level for most vehicles!

Make sure you always use the recommended PSI as provided in your owner’s manual and don’t go any more than 5 PSI over the recommended level. You should make sure, however, that your tires are appropriate for your vehicle. You can do this by checking the car’s owner’s manual or the placard that is on the inside of the driver-side door, glove box, or fuel door.

Most car tire pressure recommendations range from 30-35 PSI.

How often should I check tire pressure?

A question in many minds is when is the appropriate time and frequency for checking and inflating vehicle tires.

A quick google search will reveal a variety of different opinions and suggestions. Some say that you should check your tire pressure every 2nd visit to the gasoline station, while others say once every 3-6 months is OK.

Most tire and vehicle manufacturers, on the other hand, will say that you should check your tire pressure at least once every month, or every second trip to the gas pump. Your tires will lose around 1 PSI each for every month that goes by.

Unfortunately, not one answer will fit every situation. There are several factors that influence how often you should check your tire pressure, including:

  • The weather (hot and cold seasonal changes)
  • Driving frequency and distance
  • Weight carried or towed

Did you know that for every 10°-drop in temperature, you lose 1 pound of pressure?

If you have a leaky valve or a small puncture, you will lose air pressure much more quickly. This is one more reason why you should frequently check the tire pressure on all of your tires.

Since tire pressure constantly fluctuates, it’s important to check it periodically (at least once a month) and add air as necessary.

How to Check Tire Pressure

Finding out the tire pressure of your tires is incredibly easy. All you need is a pressure gauge (click here for additional items you should have in your vehicle).

Just make sure that you are checking your tires when they are relatively cold. If you check your tire pressure after a long drive, you will get an inaccurate reading since heat will temporarily increase the tire pressure reading.

Unfortunately, not all pressures gauges are created equal. Some are better than others. We recommend shelling out a couple extra bucks for a digital reader. The pop-up, stick-type versions are notoriously inconsistent and unreliable. A reliable gauge will be well worth the investment. Prices range from about $5 for the stick-type and about $30 for the digital and dial-type pressure gauges.

You can also check your tire pressure at most gas stations or auto repair shops. Discount Tire offers free tire pressure checks and inflation.

Here are the steps for checking your tire pressure:
  • Check the tire pressure when the tires are cold—first thing in the morning is best. If you’ve been driving for a while, you’ll want to wait several hours before checking your tire pressure.
  • Remove the caps to your tires’ air valve (keep them in a safe place, like your pocket).
  • Place the tire pressure gauge on the air valve firmly to receive a reading.
  • Take the tire pressure reading 1-3 times to get a good average and reduce the risk of anomalies.
  • Check the tire pressure gauge reading against the recommended PSI levels recommended by the manufacturer.
  • Add some air until your reach the recommended PSI level.
  • If the reading is above the recommended PSI level, push down on the air valve to release air. Check the tire pressure again. Release more air if necessary. If you release too much air, you can always add some air back.

It should only take you a couple minutes to check the air pressure of your vehicle’s tires. As soon as you restore tire pressure to the recommended levels, you’ll start experiencing the safety and savings that come with this regular maintenance task.

Watch this video for more information on how to check your tire pressure:

How to Inflate Tires

Here are the steps for adding air to your tires:

  • Remove the valve stem caps on all of your tires (keep them in a safe place, like your pocket).
  • Use an air pump to fill the tires. Even though it’s possible to fill your tires with a regular old bicycle pump, this is not the most efficient method. Instead, go to your local gas station that has a coin-operated air pump (ask the attendant if you can’t find it). You can also purchase your own automatic air compressor, but it will cost you around $50-$150.
  • Inflate your tires when they are cold. If you’ve driven more than a couple miles, you’ll want to wait until they are cold. The best time to refill your tires is first thing in the morning.
  • You can usually set the desired PSI level on the machine at the gas station (probably around 30-35 PSI). If your local gas station’s air pump doesn’t have this capability, then you will need to fill up the tire, check the pressure with your gauge, and then add or release air as necessary. Some air pumps will have a built-in tire pressure gauge. Once the PSI level is set, feed coins into the machine until you hear the air coming through. It will be pretty noisy.
  • You want to act quickly because you only have a few minutes before the pump turns off. Bring the tip of the air valve to your closest tire valve (or the lowest tire). Hold it firmly against the valve as you listen to the air filling the tire.
  • Make sure your vehicle is close enough to the pump so you don’t have to move and pay for another air session.
  • Give the pump some time to fill up your tires. If you pre-set the PSI on the machine itself, you will hear a loud beeping noise when the desired PSI is reached. If not, fill up the air for around 5-10 seconds and then check the tire pressure with your pressure gauge. Check the air pressure as you go and refill or release air as necessary.
  • If you go over the recommended PSI, you can release air from the tire by depressing the center valve pin with your tire gauge or a similar tool (a fingernail can also do the job). Release the air in small increments and check the pressure as you go.
  • When you have reached the desired pressure, make sure you check all your tires again with your pressure gauge. If all is well, you are done adding air.
  • Remember those valve caps we told you to keep safe. You’ll want to screw them back on now.

Remember, just one drop in PSI can lower your gas mileage by about 0.2%. For every 3-4 PSI units that your tire is underinflated, you are burning around 1% more fuel.

If your tires are flat, then you probably have a leak. Add air and see if you can drive around without the pressure dropping. If you hear air escaping the tire while you are filling up, then it’s time to replace the tire.

Tip: Learn how to use the air pump properly first. Some automatic air pumps at gas stations have a handle/switch that you need to depress in order for the air to flow. When you let go of the handle, a tire pressure gauge will pop out showing you the tire pressure. At the same time, air will be slowly released. If your air pump has this kind of handle, then you will want to hold down the handle for most of the time, periodically releasing it to check the pressure reading. Consult your own tire pressure gauge for accuracy.

When should I replace my tires?

If you check your tire pressure at least once a month as recommended, you’ll also get a good idea of the general condition of your tires and when you should replace them.

We recommend using the penny test:


  • Take a penny and insert the top part of Lincoln’s head (head down) into one of the tire treads. If you can see his entire head, it’s time to replace your tire immediately.
  • Consider a replacement soon if only a small part of his head is cut off. You are good to go if Lincoln’s forehead is covered. Use the penny test on a few areas of each tire to get a more accurate reading.

Click here for more car maintenance tips. Click here for car winterization tips.

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More from Auto Simple

How to Properly Inflate Your Car Tires

Your car's tires play many valuable roles in the safety and function of your vehicle — from helping you navigate twists, turns, and stops like a pro to carrying the full weight of your car. That's why it's important to pay special attention to these essential components.

Fortunately, maintaining the proper tire pressure on your vehicle is one of the easiest yet most effective ways to care for your car tires. Learn how to check air pressure and inflate your tires with this helpful guide.

Why is Tire Pressure Important

Underinflated tires can not only reduce fuel efficiency, but it can also run the risk of getting into an accident, losing proper steering control, damaging various components of your vehicle, and more. If you notice that your tire's air pressure levels have dropped, it's best to prioritize inflating them as soon as possible.

How to Check Tire Pressure

Checking your vehicle's tire pressure is a relatively simple task. You'll want to start by purchasing a tire gauge. These vary in price depending on the type you choose (i.e., digital, basic, etc.) but can usually be found for well under $40. It's also essential to keep a tire gauge on hand, as some gas station air hose gauges are not always accurate. Many modern cars and trucks also display the tire pressure for each tire on the dashboard. Once you have your tire gauge in hand, it's time to determine the proper pressure for your vehicle. 

    Find the correct inflation level. To do this, you can either look for the recommended pressure on the sticker within your driver's-side door jamb or consult your car owner’s manual. This is the tire pressure specification when the tires are cold, meaning not driven for a few hours.

    Remove the valve stem cap from your tire. Some cars and trucks have green valve stem caps with an “N” on them - this means the tire is filled with nitrogen instead of air (air is mostly nitrogen). If your tires have these green valve stem caps, you can find some special stations that dispense nitrogen, but be aware that you can use normal air as well. The inflation pressure specifications are the same regardless if the tire is filled with air versus nitrogen. 

    Connect your air pressure gauge to the tire’s valve stem until you receive a reading.

    If the pressure level number seems unrealistic, remove the gauge and try again. This time, ensure that the indicator is connected firmly to the valve stem.

    It's not always possible to tell if a tire is underinflated by giving it a quick once over. So, check your PSI levels with a gauge each month and after extreme temperature changes. You'll also want to check your pressure levels when your tires have had time to cool down since air expands within your tires while driving.

    How to Inflate Your Car Tires

    How to Inflate Car Tires at a Gas Station

    Filling your tires with air at a gas station is relatively simple. Bring your tire gauge and some spare change since some are coin-operated and are not always accurate in their pressure readings. Try to make this the first stop if you are running errands so that your tires are still relatively cool from sitting for a few hours. Then, follow these steps:

    1. Park your vehicle close to the air dispenser so that you can comfortably reach each of your tires with the hose.
    2. Remove the valve stem caps from each tire.
    3. Use your tire gauge to check the air pressure in each tire.
    4. If the pressure is low, begin by adding air (one tire at a time) with the hose. 
    5. Stop periodically to ensure you haven't overinflated your tires. If you do overinflate, release some of the air slowly until you reach the proper amount.
    6. Replace tire valve caps once you've gotten them to the appropriate pressure levels.
    7. Enjoy the ride, and continue to monitor your tire pressure regularly.

    How to Inflate Car Tires at Home and On-the-Go

    1. Find a level surface under the shade.
    2. Remove the valve stem caps from each tire.
    3. Use your tire gauge to check the air pressure in each tire before starting. Remember that the tire temperature and air pressure will rise as you drive.
    4. If the air pressure is low and you have access to an air compressor at home, firmly press the air-hose onto your tire valve stem. You should start to hear air entering the tire. If not, confirm that the air hose and your tire’s valve stem are both securely connected.
    5. Try not to overinflate your tires. If you do, slowly release some of the air until you reach the correct amount of air.
    6. Replace the caps.

    Inflate Your Tires with Firestone Complete Auto Care

    Can't find an air filling station near you or just want some help? Head to your local Firestone Complete Auto Care. We'll give you a free tire inspection and refill your tires free of charge. And if you need new tires, we've got you covered there too!

    How to inflate tires in a car?

    Tire inflation is an extremely important aspect, although many think otherwise. If you want your tires to provide safety and optimal working conditions, you should take care of the correct tire pressure. It is recommended that you check your tire pressure regularly to prolong the life of your tires. So how do you properly inflate your tires so you can ride longer?

    Why do tires run out of air?

    The pressure drop in car tires is influenced by many factors, such as mechanical damage or errors during wheel assembly. It is worth paying attention to the valves, especially their tightness, which is often in doubt. The correct tire pressure is of great importance, on which the service life of the tire, comfort and driving safety ultimately depend.

    The weather conditions that surround us are also important. In winter weather and freezing temperatures, we can see that tire pressures are often too low. In such situations, we recommend that you inflate your tires as soon as possible at a petrol station or vulcanizing shop.

    Moreover, it is worth arming yourself with a pressure gauge, thanks to which we will carefully monitor the level of pressure in our tires, and the “by eye” method itself may simply be ineffective.

    Want to inflate your tires yourself? Follow the instructions in this article

    How to inflate car tires?

    Tire inflation is easy. Of course, you must stand close to the circle, take the gun and insert the hose into the valve, while keeping the latch pressed. When the tube is placed on the valve, pull the trigger. After inflation, release the trigger, press the latch on the tube and pull it out vigorously.

    The tire is usually inflated to about 2 bar, but it is always worth checking the manufacturer's recommendations, which are available, for example, on the front door near the lock or on the gas tank flap. Poorly inflated tires result in poor traction, faster tire wear and reduced damping.

    Correct tire pressure

    To check the correct tire pressure, just look at the information on the fuel filler flap or on the door. There we will see information about the recommended pressure in the case of a standard and full car load. When checking tires, analyze the "Max. pressure" label, which informs us of the maximum pressure for our tire.

    In this case it is 340 kPa. If you want to read your data in bars, move the decimal point two places to the left and out of 340 kilopascals you get 3.4 bars.

    How to pump air?

    Here you have to choose between a slightly innovative method, i.e. filling the tires with nitrogen, or something more traditional, i.e. atmospheric air. However, it is worth remembering that in order to fill tires with nitrogen, you usually have to go to a car repair shop.

    In this case, this entails additional costs in the amount of PLN 5 to 8 per tire. However, in the long run, such a solution can be beneficial, especially when we have a large number of cars.

    Nitrogen - dry gas without oxygen. It does not contain moisture, so a tire filled with it benefits significantly in terms of durability. What's more, nitrogen helps reduce fuel consumption, especially on long journeys.

    Nitrogen filled tires reduce the risk of lumbago for increased safety. It is estimated that tires filled with nitrogen last three times longer than those filled with air. This solution is often used in racing cars.

    Pressure transducers

    Pay attention to the correct tire pressure in different units. Usually these are bars (bar) or kilopascals (kPa), less often atmospheres (at) or pounds per square inch (psi), which are used in the Anglo-Saxon system of measurement. Take a look at our converter.

    Inflating car tires at a gas station

    Are you wondering how to inflate tires on the road, but don't have the right equipment for this? One solution - and it's free - could be a gas station. Here you can refuel or inflate tires. In this matter, we simply set the appropriate value on the device, and then we put the cable on our car valve.

    The use of this type of compressor is extremely simple. Moreover, the stations often have an instruction manual for such a compressor.

    How to properly inflate tires

    Watch the temperature of the tires - the tires must not be very hot before inflating. Choose the right moment and wait about 30 minutes for the tire temperature to stabilize.
    Car customization - no matter how you customize yours. The hoses at the stations are very long and usually coiled to easily reach the wheel of the car.
    Bleed some air - start by bleeding the tires. Thanks to this, you can be sure that there will be no dirt left in the tire, which over time can penetrate the inside of the tire.
    Inflating a damaged tire. If you suspect that your tire structure is damaged, do not inflate the tires. A damaged structure can lead to tire burst. For safety reasons, move away from the vehicle while pumping.
    Tightening the nut is a minor drawback, but tightening the nut limits the amount of air that can escape through the valve.

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    Basic rules for inflating car tires

    Every driver at least once in his life faced such a problem as a flat tire. If it is not corrected, then in the future such a careless attitude can lead not only to a decrease in comfort during the movement of the vehicle, but also to an emergency. In addition, if the pressure in the wheel is not observed, there is an additional load on the parts of the chassis and even influence on the rest of the vehicle, which reduces its service life. Everything is interconnected in the car and therefore it is simply necessary to monitor the condition of even the tires, pump them up in a timely manner and carry out a systematic inspection.

    Experienced drivers are already familiar with the procedure for checking and inflating tires, but beginners are not always able to do everything right the first time. Let's try together to analyze all the nuances and pitfalls in this article.

    Why it is necessary to maintain tire pressure in the norm

    When buying car tires, the manufacturer himself indicates in the instructions what pressure should be maintained. If the documents have been lost, then the information may be contained on the company's website or freely available on the Internet, it is not difficult to find it. This is a very important parameter, which greatly affects the performance and service life.

    In addition, reduced pressure contributes to greater fuel consumption, which significantly hits the owner's pocket. Other problems arise, for example, grip on the road is reduced, accidents are possible, which reduces driving safety. In simple words - driving becomes more difficult.

    It is often possible to observe such a picture when, with a significant decrease in pressure, the rim cuts through the side of the tire or wear occurs much faster. These are just a few of the problems, the list is much longer.

    But it is also impossible to pump the tire, as the wheel will start to wear unevenly, the tread in the middle part will wear off quickly or braking will become less effective. This is unacceptable. Another disadvantage of an overinflated tire is the possibility of the wheel exploding, resulting in tire failure, loss of control, and collisions in busy traffic on the road.

    How often to check tire pressure

    Professionals and experienced drivers recommend checking tire pressure at least once a month. During a cold snap or heavy rainfall, the number of checks should be increased, usually 1 time in 10-14 days is enough.

    If you are planning a long trip, you should also check everything in each wheel before departure. It is better to prevent a problem than to deal with the consequences.

    When the car is rarely used, it is better to inspect all wheels before getting behind the wheel and, if there is even the slightest sign of a decrease in pressure, check the indicators and perform pumping. If desired, this procedure can be repeated with daily, intensive use of the car.

    Important! Tire pressure must be the same on all wheels. Neglect of this rule may affect the handling of the vehicle. Don't forget about the spare wheel too.

    Where can I find information about the correct tire pressure for your specific vehicle?

    As mentioned above, you can read the manufacturer's recommendations in the documents that come with their product. They have already experimentally calculated the allowable norms. The same information can still be found in various places on the vehicle or in the instruction manual for the vehicle itself.

    Inspect the A-pillar in the car or the inside of the gas door. Tables are placed there, sometimes a similar sticker can be found on the doors of individual brands. See the necessary indicators and maintain pressure. There should be no difficulty in reading the table.

    In extreme cases, you can always ask specialists in workshops or contact the manufacturer's consultants, or search the Internet.

    When you can inflate the wheels

    There are rules for pumping, which must be observed. It is important not only to know the rate of pressure, but also when the conditions must be met. So the wheel can only be pumped up after the car has been at rest for a long time, because the tire heats up while driving, and the indicators may be inaccurate. Since school, the fact has been known that temperature directly affects gas pressure.

    Usually 3-5 hours is enough, it is better when the temperature of the tire is the same as the environment. It also depends on the weather conditions, or the room where the car is located.

    This is the only way to know the exact pressure readings and top up if necessary. As an option - do a pressure measurement and pumping in the morning, after an overnight stay.

    How to inflate a wheel with your own hands

    At first glance, everything is simple, but novice drivers may have questions. To do this, you must have a pump on hand, as practice shows, most motorists take a foot pump for this purpose. It is much cheaper than compressors, but it is more difficult to control the pressure level and you will have to make physical efforts. The compressor already includes a pressure gauge, the design is more complicated and therefore it is more expensive. There are a large number of companies on sale with various additional functions and even with the ability to work from the cigarette lighter.

    We're looking at a foot pump and a tubeless tyre, so the pressure gauge needs to be taken care of as well. The whole process can be divided into stages, which will greatly simplify understanding and you will definitely do everything without problems:

    1. The place for pumping must be flat, it is necessary to move off the roadway and put the car on the handbrake.

    2. We take out a manometer, a foot pump (if it is electric without a battery, we connect it with a cord). They must be in working order, without signs of severe damage.

    3. Next, unscrew the cap on the nipple, which is located on the splint. We put it in a pocket or in a conspicuous place, its loss is highly undesirable.

    4. We connect the pump hose to the nipple, put it on completely, until the whistle stops (observed when air comes out of the tire).

    5. Handpiece handle rotated 90 degrees to secure.

    6. We check the pressure readings with a pressure gauge, they should be within normal limits. If necessary, pumping use a pump.

    7. Pump up and check with a pressure gauge. If the desired limit is reached, then remove the hose tip and quickly (necessarily carefully) screw the cap onto the tire nipple.

    The whole procedure is carried out on 4 wheels and spare.

    With a compressor, with a function on it that allows you to stop the device when the desired numbers are reached, everything is faster and easier, it is almost impossible to make a mistake.


    A simple pumping process can be quickly mastered, the main thing is to remember all the rules and the necessary pressure parameters for your specific case. Special knowledge and skill is not required, as well as great physical strength. It is not necessary to visit expensive workshops, it is enough to have the equipment at hand and conduct inspections on your own. You can save a lot and protect yourself from emergencies and possible consequences, such as high fuel consumption and buying a new wheel due to improper abrasion or explosion.

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