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Maintenance

How to check tyre pressure correctly

Find the right PSI/bar from the door sticker, check pressures cold, and stop using the sidewall maximum — the #1 tyre Google mix-up.

Time:
10–15 minutes
Level:
Beginner
Videos:
2 how-tos

Before you start

Under-inflated tyres waste fuel, wear the shoulders and fail MOTs; over-inflated tyres wreck the centre tread and reduce grip. The number moulded on the tyre sidewall is the maximum the tyre can take — not what your car needs. Google “correct tyre pressure” and the door-pillar sticker is the answer people actually need.

What you’ll need

  • Accurate pressure gauge or air compressor with gauge
  • Door-pillar or fuel-flap pressure label
  • Valve caps
  • Optional: MotorTools tyre pressure converter for PSI ↔ bar

Watch a good how-to

Popular walkthroughs that match this job. Watch for technique — always follow your handbook for torque figures, jacking points and fluids.

How to Check and Inflate Car Tyres

Halfords UK · Short official UK walkthrough — gauge, sticker pressures and topping up cold.

Open on YouTube ↗

How To Check Car Tyre Tread Depth And Pressures Are Correct

Practical Motorsport · Door-sticker pressures plus legal tread depth context for MOT.

Open on YouTube ↗

Step-by-step guide

  1. 1

    Check pressures cold — before a long drive, or after the car has stood for a few hours. Warm tyres read higher.

  2. 2

    Read the vehicle sticker (driver door shut or fuel flap). Note different figures for load / motorway and for front vs rear.

  3. 3

    Remove the valve cap, press the gauge squarely, and compare to the sticker. Inflate or let out air to match.

  4. 4

    Refit caps. Repeat on the spare if you have one (space-savers often need higher pressure).

  5. 5

    Re-check weekly or before long trips, and after hitting potholes or kerbs.

  6. 6

    If a tyre keeps going down, have the rim, valve and tread inspected — do not just keep adding air.

What to check

  • Legal tread depth is generally 1.6mm across the central three-quarters of the tread — pressure does not fix a bald tyre.
  • TPMS lights need a cold pressure check even if the tyre “looks fine”.
  • Reset TPMS procedures vary — handbook after correcting pressures.

Pro tips

  • Keep a compact digital gauge in the glovebox — petrol-station gauges vary wildly.
  • Matching brands and similar tread depths across an axle helps stability.
  • EV and performance cars often run higher pressures — trust the sticker/app, not a mate’s Fiesta settings.

FAQs

PSI or bar?

UK stickers may show either or both. Use one unit consistently. Our tyre pressure tool converts between them.

Should I raise pressure for motorway trips?

Only if the sticker has a loaded / high-speed column. Do not invent a +6 PSI rule that conflicts with the manufacturer label.

Why did pressure drop overnight in winter?

Cold air contracts. Recheck cold against the sticker; a large ongoing loss still means a leak.

Safety first

Do not drive on a soft tyre at motorway speed. If the sidewall is bulged or cords show, replace the tyre — sealing kits are for small tread punctures only.