Goofy Tire Mystery

[1saxman]

Okay, I had noticed that my left front was looking a little low, so naturally I procrastinated on looking at it. After some weeks, I finally gauged it to find only 16.5 psi. I got the compressor out and pumped it up to 33.5, my usual. Then I went and got my eyeglasses and a piece of chalk and started looking for a nail - nothing was to be found. I got my tire valve kit and checked for a loose valve - no problem found. Okay, I'll check it tomorrow and keep an eye on it. It's now a week later and it hasn't lost enough air to register on the gauge. I am now faced with the possibility that the last time I 'adjusted' my tire pressure, I must have screwed up, although I can't imagine how I didn't see that the tire was low. All the other tires on it and the other two vehicles checked out okay. If somebody had let air out of the one tire, they probably wouldn't have only let a little out then put the valve cap back on (straight, too, not cross-threaded), so that's out. There is no scenario that allows a tire to leak down one week but not the next, so 'who dunnit'?:ghost:

[newbievueowner]

I say you have a nail or something in your tire. Use a soapy water solution and a spray bottle. At 35 PSI, the puncture area should cause the soap solution to start bubbling. Good luck

[onefunkar]

one of my daughter had the same thing last year on a pre tpms car. . tires 32 31 32 17... filled it up and its never gone down. i also thought someone may have let out the air but wouldnt put the cap back on.

[1saxman]

Hey newbie; in 45 years of driving, I've had plenty of nails, screws, blowouts, tread/belt separations and anything else that can happen to a tire. I've done the water trick and seen it done many times (for bicycle tubes too). But, for this to work, there has to be air leakage. If the tire doesn't go down a little over several days (adjusting for tire temperature at the time of gauging), there technically isn't any leakage, so there would be nothing to make bubbles. Plus, nails and screws have heads which are usually painfully obvious upon even a casual examination. Of course, there's the possibility that there's a nail-type object in the tire that has no head and is just below the rubber surface. This would be found with the water test if there was air leakage.
This time of year used to be called 'The Silly Season' by local newspaper men because news got so slow, with vacations and hot weather, that they had to really dig for stories. They printed lots of stuff that would've been too 'silly' for regular use. I'm starting to think I've just contributed to 'Silly Season' with this goofy thread.

[Tom92SCm]

Prior to noticing the low air pressure, did you do any driving off road or take any corners fast or maybe drive through some muddy water?

I'm just thinking that maybe something got between the wheel and the beed of the tire and allowed some air to escape and then after being driven on for awhile with low pressure, the flexing of the tire allowed whatever was in there to work its way out and the tire resealed itself against the wheel.

I've seen something similar at the track. A car goes off track sideways through the grass with low profile tires and gets a bunch of grass and dirt in the beed. Tire goes flat. They get it back to the paddock and get the tire unmounted, wheel cleaned and tire put back on. This is a pretty extreme case, but perhaps something similar happened to you, only on a much smaller scale.

That's all I can come up with.

[newbievueowner]

Hey newbie; in 45 years of driving, I've had plenty of nails, screws, blowouts, tread/belt separations and anything else that can happen to a tire. I've done the water trick and seen it done many times (for bicycle tubes too). But, for this to work, there has to be air leakage. If the tire doesn't go down a little over several days (adjusting for tire temperature at the time of gauging), there technically isn't any leakage, so there would be nothing to make bubbles. Plus, nails and screws have heads which are usually painfully obvious upon even a casual examination. Of course, there's the possibility that there's a nail-type object in the tire that has no head and is just below the rubber surface. This would be found with the water test if there was air leakage.
This time of year used to be called 'The Silly Season' by local newspaper men because news got so slow, with vacations and hot weather, that they had to really dig for stories. They printed lots of stuff that would've been too 'silly' for regular use. I'm starting to think I've just contributed to 'Silly Season' with this goofy thread.
Well, keep an eye on it. If the pressure is down in 3 or 4 days then you still have a leak. I have seen small nails in a tire with the head wore off so you can barely see it. It will seal the puncture for the most part but will leak ever so slightly. There is a 'special' pucture liquid that can be used for finding the smallest leak. Sorry but I don't know the name of it, my mechanic buddy uses it. It's pretty amazing stuff. The other thing you can do is temporarily pump the pressure up to 45 psi and spray with soap. The higher pressure will help amplify the puncture leak if there is one. You can spray the bead as well to see. Or, I guess as you said, you could have improperly got the pressure number wrong when filling the tire??

[VTchemist]

I too had a similar tire occurrences in summers past. I would fill up the one low tire and it would do just fine until late fall. The culprit was a really, really small nail. The head was broken off, so it was really hard to see.

My local tire store found it and repaired the tires.

Both times, the nail came from "cleaning" my garage workshop. I swept the floor, but missed the nails. This happen twice.

I now have a very large magnet that I drag around the garage area after I "clean" my bench.

[far2grumpy]

. There is no scenario that allows a tire to leak down one week but not the next, so 'who dunnit'?:ghost:

I had a 99 Grand Caravan with one tire that'd do something similar. I got tired of listening to the better-half complain and took to local tire shop. They dismounted the tire from the alloy wheel and found corrosion in bead area. They cleaned wheel and tire and the pressure held for at least another year ... until I traded.

Incidentally, the tires were Michelin and the tire shop guy - he'd been in business since I moved to this area (24 years) - claimed Michelin tires have properties that tend to corrode alloy wheels worse than other tires.

Sounded like hocus-pocus at the time, but it struck a nerve, as I don't even look at Michelin's when I'm in the market for new tires.

[3RedLines]

I had a van that would leak air intermittently. Sometimes it would go for weeks then leak out overnight. After awhile I figured out that the valve stem was always at the 9o'clock position every time I had to air it up. Turns out it was a corroded rim that leaked around the bead when pressure was applied in a certain area.

I agree with F2G on the Michelins ...long story

[1saxman]

Good tips. gents! I'm watching and waiting now. Chances are it's a very slow leak, the slowest I've had. The next time I have to add air, it's going to the tire shop for a plug.

[emsvitil]

Depending on where the nail is when you park, a small nail may or may not leak............

[1saxman]

That's true. A lot of punctures will only leak as the tire rotates too. It's a goofy business. My favorites are the nails/screws that won't leak at all - until the novice car owner pulls them out.

[VTchemist]

Incidentally, the tires were Michelin and the tire shop guy - he'd been in business since I moved to this area (24 years) - claimed Michelin tires have properties that tend to corrode alloy wheels worse than other tires.

Can you elaborate on this? I've never heard about this.

[far2grumpy]

Can you elaborate on this? I've never heard about this.

Actually thats all I know ... the fellow claimed almost every alloy wheel they burnish due to corrosion had a Michelin mounted. I noted he sold several brand of tires ... with Goodyear being prime mover.

Are you aware of any chemical properties that could cause a particular tire brand to react to alloy wheels?

[1saxman]

Grumpy's in Iowa and they use a lot of salt on the roads. Just maybe there's something about the Michelins design in the bead area that lets the chemicals get in more than other tires. Here in VA, although they use salt in conditions where the road will get icy or snow-covered, it's not a continuous thing during the winter, and some winters you won't see any. I have never seen any corrosion in the bead area on aluminum wheels here, but that would be only my own wheels.

[1saxman]

Update: The tire continued to look okay, but I started to think it was getting low, so I checked it this morning and found it to be at 24.5 psi. It took it from July 15 to lose 7.5 psi. That's a very slow leak.
ETA: The other tires maintained their pressure.

[04moranjames89]

Okay, I had noticed that my left front was looking a little low, so naturally I procrastinated on looking at it. After some weeks, I finally gauged it to find only 16.5 psi. I got the compressor out and pumped it up to 33.5, my usual. Then I went and got my eyeglasses and a piece of chalk and started looking for a nail - nothing was to be found. I got my tire valve kit and checked for a loose valve - no problem found. Okay, I'll check it tomorrow and keep an eye on it. It's now a week later and it hasn't lost enough air to register on the gauge. I am now faced with the possibility that the last time I 'adjusted' my tire pressure, I must have screwed up, although I can't imagine how I didn't see that the tire was low. All the other tires on it and the other two vehicles checked out okay. If somebody had let air out of the one tire, they probably wouldn't have only let a little out then put the valve cap back on (straight, too, not cross-threaded), so that's out. There is no scenario that allows a tire to leak down one week but not the next, so 'who dunnit'?:ghost:

somebody let the air out on my dad's 05 altima. ALL OF IT! so when he went to back out of the driveway it was all rim. i dont even think they put the cap back on, does it matter though?