Digital Tyre Pressure

[Sagitar]

Maybe both gauges are out? ;)

What standards, and accuracy, if any, do the tyre pressure gauges sold to us have to meet?

The EEC spec is in bar, but I seem to recall that it amounts to just over 1 p.s.i in a gauge measuring up to 60 lbs. So a gauge on the top tolerance could measure more than 2 p.s.i. different from a gauge on the bottom tolerance. And the error need not be in a consistent direction so you will get different levels of error in different parts of the scale.

I think the issue of the EEC "mark" is based upon type testing rather than the calibration of each individual gauge and I doubt whether many of the cheap "pencil" type gauges meet the standard.

You can of course buy better quality gauges with a calibration certificate, but even they will only be accurate for a time.

Tyre inflation is not an exact science anyway. The important thing is to check regularly and make sure that your tyres are never under-inflated.

[timberwolf]

Even if I am vaguely aware that there must be various factors such as temperature that affect the tyre pressure and that the digital gauge I've got will have it's own error, I forget that and think the gauge is correct. Assuming it reads within 1 psi - summer or winter I still put in the same psi pressure of F 38/ R 36, and I don't usually even think that it could be out, I've got a mental block that I could be measuring 39 psi but because the gauge displays 38 I am okay with that... :P

So while it may be inexact, I think I still treat it as if it wasn't [insert a "shrug" smiley here!]

[dwilson]

I carry a gauge in the car However, over a period of time I set the tyre pressures according to how the tyres are wearing. I use a tread depth gauge to check that the tyres are wearing universally accross their width. Quite often I find that my Toyota and my honda want to wear out the edges of the tyres before they wear out the middles when the pressures are set to standard recommendations using my gauge and so I increase the pressures by a few PSI until I can see a more universal wear pattern.I have also noted that when either car arrives back from servicing, the air pressures are reading at the recommended level again and so I add air to get them back to my preference.

I guess that the manufacturers like to run the cars at lower pressures in order to improve ride quality at the expense of fuel consumption and tyre wear.

I always take care to always check the tyres with the same gauge so that irrespective of that gauges accuracy, I get a consistant reading. As one of the other posters said, garage gauges can be inaccurate depending on how much use and abuse they get and how often they are calibrated against a standard.

I have a number of old gauges and have checked them all against each other by taking the pressure of the same tyre.There is 6 psi diference between the highest and the lowest reading.

Although I have an inherent curiosity as to the accuracy of the measuring instrument in reality I do exactly what Wass states above.

David

[noisyhen]

I've got one of these from Amazon.

Works well.

http://www.amazon.co...duct/B000Q4UBMW

Ordered one and was immediately impressed but the 2nd attempt at using it I couldn't get a reading on the display other than 0's.

Gave up and was preparing to return it but decided to have another go and it worked fine! Aa a matter of interest, any ideas as to what occurred?

[RelaxedDrive]

I am using this foot pump:

Laser 4411 Foot Pump Double Barrel With Gauge

And this more accurate gauge:

RACE X PROFESSIONAL TYRE PRESSURE GAUGE

Both were available on Amazon.

The foot pump turned out to be pretty accurate anyway, but it's easier to read the Race X gauge and you can 'take the pressure', remove it and then look at it.

[Jamesbelfast]

In my experience a pneumatic dial type gauge is the most accurate.

The downfall of the digital types that it relies on a consistent Battery voltage which will vary according to age and temperature so on a cold day it may give an entirely different reading just because the Battery is cold.

When buying a gauge check its acuracy. For instance one well known motoring store sells one which is accuarte to plus or minus 2 psi so in essence when new couild be as much as 4 psi askew.

Most tyre dealers will tell you that tyre wear is due to incorrect pressures so considering the cost of tyres investing £20 in a tyre gauge is cost effective.

[acetip]

The only way to know if your gauge of whatever type is accurate is to have checked by your local trading standards as i posted earlier.

if you gauge is out,then make the allowence when using

Its a waste of time saying so so gauges are only a couple of psi out cos some review says so. only safe way is have it tested say every year and its free.

[Jamesbelfast]

The only way to know if your gauge of whatever type is accurate is to have checked by your local trading standards as i posted earlier.

if you gauge is out,then make the allowence when using

Its a waste of time saying so so gauges are only a couple of psi out cos some review says so. only safe way is have it tested say every year and its free.

It wasn't a review which mentioned the discreptancy - it was the manufacturers.

What I am saying why by a new gauge that's unreliable in the first place.

Sadly my local council don't provide such a test facilty for free as they don't view it as a necessary public service.

[kithmo]

When buying a gauge check its acuracy. For instance one well known motoring store sells one which is accuarte to plus or minus 2 psi so in essence when new couild be as much as 4 psi askew.

Don't you mean it could be 2 psi askew either way, not 4 ?

I totally agree with the temperature thing. When I check mine on a cold morning using my Digital gauge, which has been sat in a cold car it can vary whilst I'm going round the car as the gauge warms up in my hand !

I don't know whether to keep the gauge in the house so it's warm or leave it in the car so it's at or near the same temp as the tyres. A new Battery in the gauge makes a difference too. It's all a bit hit and miss really.

[Opifex]

The only way to know if your gauge of whatever type is accurate is to have checked by your local trading standards as i posted earlier.

if you gauge is out,then make the allowence when using

Its a waste of time saying so so gauges are only a couple of psi out cos some review says so. only safe way is have it tested say every year and its free.

Useful info - thanks.