Tyre pressure gauge accuracy

[rongagin]

Ok so maybe I am being too ocd, but how do you check the accuracy of a tyre pressure gauge?
I have a Halfords analogue gauge which is maybe 10 yrs old also a electric 12V pump with digital readout. For Christmas my daughter bought me a new analogue tyre gauge as a little stocking filler, which I believe was about £14 from Amazon.
On my car I took readings on each
Old analogue = 32psi
Digital = 31
New analogue = 29

New one supposed to be to some standard which is within 2% = 0.64 psi

I tried an old pen type mechanical and it showed 34 btw

Probably being too picky but I did search and even expensive stuff can be out by a fair way.
Garage forecourt pumps are notoriously bad.

So ignore, get on with it and just adjust to where it feels right?
Or is there a way to calibrate easily?

[Scrump]

Like you I have few different gauges and like you found most of them to be within 1 or 2 psi of each other. The one on my inflator attached to the compressor is widely different to the others so I don’t use that gauge.
I just use one of the ones which are close to each other and don’t worry about a possible 1psi error.

[Fastpedeller]

Scrump said:

Like you I have few different gauges and like you found most of them to be within 1 or 2 psi of each other. The one on my inflator attached to the compressor is widely different to the others so I don’t use that gauge.
I just use one of the ones which are close to each other and don’t worry about a possible 1psi error.

This^, and use the one which 'repeats' consistently.
Keep a check on the tyres. If you are ever able to get a comparison with a calibrated gauge then that's worth doing (but maybe just for "peace of mind"). Probably most issues directly related to tyre pressures are caused by not regularly checking, and as a result of running at 20% or more deflated, the odd 1 or 2 PSI is not likely to be critical.

[rongagin]

I look at the readings and between the lowest to highest it is 5 psi
I wonder how many people are using a gauge that is very inaccurate?

Mind I once bought an Audi from a Audi main dealer and the front tyres were 31 instead of the 39psi they should have been. I wondered why it felt so floaty driving home.

[Mignon]

There's no such thing as the ONE ideal tyre pressure for any car anyway. The manufacturers give a suggestion but if the tread is not wearing convex or concave and you're not sliding into the boonies then it's what works for you. Worrying about a gauge being accurate to a fraction of a psi seems pointless. My gauges all read about the same. I tested my mates and 2 were the same and one was miles out. He's binned that one. I run my tyres at 32 psi on my gauge. They wear evenly and using more pressure doesn't seem to help mpg. I'm not too fussed what someone else's gauge says about them.

[Katzenjammer]

I have two tyre pressure gauges, a Race X job and a Draper as illustrated in the images below.

The Draper consistently reads 2psi more than the Race X at pressures been 28-38psi.

So which to believe, or buy a another gauge?

[Pica-Pica]

I have had a draper pencil gauge, hard to read, so accuracy is largely irrelevant.
I have a Halfords digital gauge; I doubted its accuracy, so I bought a TireTek analogue gauge. Guess what? they both read the same. The TPMS also reads the same, but only when the car has reached 20 driven miles. The Halfords one is the easiest to use.

To be honest the accuracy is not as important as the consistency of the reading. In the end, you set the car up at a starting point, then adjust the pressure to get the ride and feel you prefer for your road conditions and loading. I tend to set mine towards the fully laden pressures. Note: staggered tyre sizes have a smaller difference at the rear between light and full load than does a square set up - an advantage if you frequently go between the two loadings.

[Dogwatch]

Katzenjammer said:

I have two tyre pressure gauges, a Race X job and a Draper as illustrated in the images below.

The Draper consistently reads 2psi more than the Race X at pressures been 28-38psi.

So which to believe, or buy a another gauge?

Another vote for RaceX. The pencil-type pressure guages were always reputed to be pretty accurate though i have never compared across any of mine. More important to use the same guage for all four tyres perhaps?

[Panamax]

Pica-Pica said:

To be honest the accuracy is not as important as the consistency of the reading. In the end, you set the car up at a starting point, then adjust the pressure to get the ride and feel you prefer for your road conditions and loading.

Yes, and if your tyres wear on the edges add more pressure. If they wear in the centre, reduce pressure.

[vikingaero]

I have about 6 or 7 pressure gauges including the ones built into electric pumps.

Most of them read fairly similar - +/- 1 psi of each other. 4 of them read exactly the same. If any one of them was a wacky number out, I would discard it.