One-off reduction in tyre pressure

LeafGreen

Not sure if I need to be concerned about this or not...

A few days ago I went out to wash my car and noticed that one of the tyres was visibly deflated - not completely flat, but when I hooked my pump up it was below half where it should be - definitely well below a level I would drive with it at. It was probably a couple of days since I last used it.

I pumped it back up expecting it to be down again the next day, and started to wonder how much a replacement would cost, or if a repair might be possible - however to my surprise, it was fine - and again today, it's still fine - no discernible drop in pressure.

So I'm wondering, is there any explanation why pressure might drop significantly as a one-off event?

Yes, I have considered the possibility that a person might have let it down, but it feels really unlikely - just one tyre affected, dust cap was still screwed on properly, car is on the drive away from the road, behind another car most of the time, quiet area.

I'm wondering now whether to buy a new tyre as a precaution, or just waiting to see if it happens again. Has anyone else experienced this phenomenon?

Brilley

..for peace of mind I would drop it into a tyre specialist and get them to check it over...it may well have something in it and is sealing "at the moment", (happened to me once). It only costs a few quid to get them to check it over.

AdrianC

Had you checked the pressures recently beforehand? It's possible that, in doing so, you could have got a little bit of grit in the valve, stopping it sealing properly.

I've had similar one-offs a few times in the past.

neilmcl

School holidays, need I say more. That or you could have an issue with the valve.

How often do you check your tyres?

JGB1955

The same thing happened to me - I took the car to a local tyre place, they checked it and suggested it was a problem with the valve. Pumped the tyre back up, reset the (very annoying) warning on the in-car display and sent me on my way. That was 3 years ago - it's not happened since.

LeafGreen

Probably about a month since I last checked them. I find they normally lose about 1-2 PSI in that amount of time.

Good call I think getting them checked out. I certainly don't want to risk issues out on the road, and even a replacement is not a massive price to pay. Just slightly annoying as I replaced all 4 tyres at the start of the year!

neilmcl

I was having a problem with mine a while back, every time I checked the tyre pressure the following morning the tyre was almost flat. Took it in and as suspected the valve was sticking. The fitter didn't even charge me to change the valve.

Aylesbury_Duck

I had the same experience a couple of years ago. It was a screw that had embedded itself in the tyre but air only leaked out when it was parked with the screw at "6 o'clock". It might have been there for a while before I noticed it because the tyre would maintain pressure for days but would then lose quite a few psi in one night. After two such occurrences I got my mobile tyre guy to check it for me and he found it.

LeafGreen

Problem found - it was a screw in the tyre. Popped down to the garage just now and fortunately it was repairable so good result.