How to Check Tire Pressure

📋 Quick Facts

Tire pressure drops about 1 PSI per 10 degrees Fahrenheit of temperature drop, and also drops 1-2 PSI per month from natural air permeation through the rubber. Check monthly, and always before a long trip. Under-inflated tires cause blowouts, terrible MPG, and edge wear. Over-inflated tires cause a harsh ride and center wear.

🛠 What You'll Need

• Tire pressure gauge - digital or pencil-style (AstroAI digital tire pressure gauge on Amazon)
• Access to air - gas station or home compressor
• Optional: portable 12V compressor (VIAIR 12V tire inflator on Amazon)

✅ Before You Start - Checklist

• Park on level, solid ground (no slopes, no soft dirt)
• Engine is at the correct temperature (cold or warm as specified)
• All tools and parts on hand BEFORE you begin
• Owner's manual nearby for torque specs and locations
• Safety: gloves, eye protection if needed, hood propped open

📝 Step-by-Step Instructions

1. Find the correct PSI on the door stickerOpen the driver's door and look at the B-pillar for a yellow/white sticker labeled "Tire Information." This shows COLD PSI for front and rear tires. Do NOT use the number stamped on the tire sidewall - that is the max pressure, not the recommended pressure.
2. Check pressure first thing in the morning (cold)Tires are "cold" after sitting 3+ hours or having driven less than 1 mile. Hot tires read 4-6 PSI higher than cold.
3. Unscrew the valve cap on a tirePull the valve cap (small plastic cap on the valve stem). Put it in your pocket - they roll away easily.
4. Press the gauge firmly straight onto the valve stemHold the gauge straight (not at an angle) and press firmly until the hissing stops. A short hiss is normal - a long hiss means the gauge is not seated. Read the number.
5. Compare to the door sticker PSIIf reading matches the sticker, you are good. If it is more than 2 PSI low, add air. If it is more than 2 PSI high, let air out by pressing the small pin in the valve stem.
6. Add air at a gas station or with a compressorMost gas stations charge $1-2 for air (free with car wash often). Apply the chuck to the valve, press to add air, and re-check every 5 seconds. Easier to add too much then bleed off than try to hit exact number.
7. Re-check the pressure with your gaugeGas station gauges are notoriously inaccurate. Always re-check with your own gauge.
8. Replace the valve cap and repeat for all four tires (plus spare)Don't forget the spare - it loses pressure too. Check it every 3 months. A donut spare with low pressure is useless when you need it.

✅ After You Finish - Verify Checklist

• No tools left in the engine bay or under the car
• Test the system you worked on (start, drive, check, etc.)
• Look for leaks or drips after 5 minutes of running
• Record the date and mileage in your service log
• Recycle or properly dispose of any old parts/fluids

🔗 Related Guides

❓ Frequently Asked Questions