Tyre Pressure & TPMS: A Complete Guide for Drivers
Find out how to check your tyre pressures, where to find the correct
pressure for your vehicle, what the TPMS warning light means and why
a tyre may keep losing pressure.
Correct tyre pressure is fundamental to tyre safety, handling and tyre life.
A tyre that is significantly underinflated or overinflated may not perform
as intended and can wear prematurely.
Modern vehicles also use a Tyre Pressure Monitoring System (TPMS)
to warn the driver when tyre pressure may require attention. This Bangor Tyre
Company guide answers the most common tyre pressure and TPMS questions asked
by motorists in Bangor and across County Down.
What Is the Correct Tyre Pressure for My Car?
Do not assume the pressure printed on the tyre sidewall is the recommended
inflation pressure for your vehicle.
Where can I find my correct tyre pressure?
Recommended pressures are normally listed in the vehicle handbook or
on a manufacturer’s information label, often found inside the driver’s
door area or fuel filler flap.
Is the PSI written on the tyre the correct pressure?
Not necessarily. Information moulded into the tyre sidewall can include
maximum limits and tyre specifications rather than the recommended
operating pressure for your particular vehicle.
Follow the vehicle manufacturer’s pressure recommendations.
Should front and rear tyre pressures be the same?
Not always. Some vehicles specify different pressures for the front
and rear axles.
Does tyre pressure change with passengers and luggage?
It can. Some manufacturers specify higher pressures when the vehicle
is heavily loaded or carrying several passengers and luggage.
Check the manufacturer’s recommendations for normal and fully loaded
driving conditions.
How & When Should You Check Tyre Pressure?
Check Regularly
Make tyre pressure checks part of your routine vehicle maintenance.
Check When Cold
For the most consistent reading, check pressures before a long journey.
Check Before Trips
Check pressures before long journeys or when carrying additional loads.
How often should I check my tyre pressure?
A useful routine is to check your tyres at least monthly and before
long journeys. You should also investigate if a tyre looks low or
your TPMS warning appears.
Should tyre pressures be checked hot or cold?
Manufacturer pressure recommendations are generally based on cold tyres.
Driving causes the tyres to heat up and their internal pressure to rise.
Should I check the spare tyre?
Yes, if your vehicle carries an inflatable spare wheel. A spare that
has lost pressure may be of little use when you actually need it.
Can I rely entirely on my TPMS?
No. TPMS is an important warning system, but it should complement rather
than replace routine manual tyre inspections and pressure checks.
What Happens When Tyre Pressure Is Too Low?
Is low tyre pressure dangerous?
Significant underinflation can adversely affect the way a tyre behaves.
It increases tyre flexing and can generate additional heat while driving.
It can also affect steering, braking behaviour and tyre wear.
Does low pressure wear tyres faster?
Underinflation can produce abnormal wear patterns and shorten the usable
life of a tyre.
Can low tyre pressure affect fuel economy?
Underinflated tyres can increase rolling resistance, meaning the vehicle
may require more energy to maintain its speed.
Why does one tyre look lower than the others?
It may simply require inflation, but repeated pressure loss can indicate
a puncture, valve leak, wheel issue or another problem requiring inspection.
Can Tyre Pressure Be Too High?
What happens if I put too much air in my tyres?
Overinflation changes the tyre’s shape and contact with the road and can
influence ride comfort, grip and wear.
Tyres should therefore be inflated to the pressures recommended for the
vehicle rather than simply made as firm as possible.
Does higher pressure make tyres last longer?
Not necessarily. Excessive pressure can itself contribute to uneven wear.
Correct inflation is the objective.
More pressure is not automatically better. Use the pressure specified by
the vehicle manufacturer and adjust it when required for the vehicle’s load.
What Does the TPMS Warning Light Mean?
Check the tyres and pressures to establish why the warning has appeared.
What is TPMS?
TPMS stands for Tyre Pressure Monitoring System.
It is designed to alert the driver when the system detects a tyre
pressure issue.
Why has my tyre pressure warning light come on?
Possible causes include:
- One or more tyres losing pressure
- A puncture or slow leak
- Temperature-related pressure changes
- A TPMS sensor or system issue
- The system requiring reset after pressures were adjusted
What should I do when the TPMS light comes on?
Check the condition and pressure of all tyres as soon as it is safe
to do so. Inflate them to the manufacturer’s recommended pressures
where appropriate.
If a tyre continues losing pressure, it should be inspected.
Why is the TPMS light still on after inflating my tyres?
Some systems need to be reset or driven for a short period before
recognising the corrected pressure.
If the warning remains, there may be an ongoing pressure problem or
a fault within the monitoring system.
Can a TPMS sensor fail?
Yes. TPMS sensors and their batteries can eventually develop faults.
A persistent warning does not therefore always mean that the tyre itself
has a puncture, but it should still be investigated rather than ignored.
Why Does My Tyre Keep Losing Pressure?
Why do I keep having to put air in the same tyre?
Repeated pressure loss indicates that the cause should be investigated.
Possible sources include a small puncture, leaking valve, wheel corrosion,
damaged wheel or a sealing issue between the tyre and rim.
Could I have a slow puncture?
Yes. Small nails and screws can create slow leaks where pressure drops
gradually over days or weeks rather than the tyre immediately becoming flat.
Can the tyre valve leak?
Yes. Pressure loss can originate from the valve or valve assembly rather
than the tyre tread itself.
Can an alloy wheel cause a tyre to lose pressure?
Wheel damage or corrosion around the tyre bead area can sometimes
contribute to air leakage.
Don’t keep treating repeated pressure loss simply by topping the tyre up.
Finding the cause early may allow a straightforward repair and helps avoid
driving on an underinflated tyre.
Does Cold Weather Affect Tyre Pressure?
Why does tyre pressure drop when it gets colder?
The pressure of the air inside a tyre changes with temperature.
As temperatures fall, tyre pressure can also decrease.
This is one reason pressure warnings can become more noticeable during
colder weather.
Should I check my tyres more during winter?
Regular checks are important throughout the year, but changing seasonal
temperatures make tyre pressure particularly worth monitoring during
autumn and winter.
Can warm weather increase tyre pressure?
Yes. Pressure naturally rises as the tyre and the air inside it become
warmer, including during normal driving.
Should I let air out of a warm tyre?
Avoid adjusting a warm tyre solely because its reading is above the
manufacturer’s cold-pressure figure. Where possible, check pressures
when the tyres are cold.
Tyre Pressure & TPMS Checks in Bangor
Where can I get my tyre pressure checked in Bangor?
Bangor Tyre Company can inspect your tyres and help identify problems
associated with pressure loss for motorists in Bangor, County Down and
the surrounding area.
Can you investigate a tyre that keeps losing pressure?
Yes. Repeated pressure loss can have several causes. Inspection can
determine whether the problem is a puncture, valve, wheel or another
tyre-related issue.
Can you check the condition of my tyres as well?
Yes. Pressure should be considered alongside tread depth, tyre wear,
visible damage and overall tyre condition.
What if my tyre has a puncture?
If a puncture is found, the tyre can be assessed to establish whether
it falls within the permitted repair area and is otherwise suitable
for professional repair.
Concerned About Your Tyre Pressure?
If your TPMS warning light is on, one tyre keeps losing pressure or you are
concerned about the condition of your tyres, visit Bangor Tyre Company for
professional tyre advice in Bangor, County Down.