Corolla tire leakage

Soapy water over the tire to see if you find a leak that way. Take the cap off to see if it's from the core.

Tires with slow leaks not caused by punctures or cracking are:

1. Leaking through the valve stem
2. Leaking through the valve core
3. Leaking through a dirty bead
4. Leaking through a puncture or crack that you missed.

I suggest putting a metal cap over the valve and see if that stops it. If it's leaking through the valve core, that is not a great permanent fix, but it's a good diagnostic tool and you should keep the metal caps on there anyway because it's cheap protection against future leaks.

--scott

If the manual tire gauge agrees with the pressure sensor then the pressure sensor is ok. You did not say if it is always the Same tire - will assume so. Every time I had that problem there has been a nail or screw in the tread. The left rear of my Kia had that problem for last two years and I finally upped the air pressure to 40+ and soaped it. Found the screw and removed it with needle nose pliers and then plugged it.

The red light just says I NEED AIR. The gauge on the pump and on my nifty little talking digital one are never the same -- I've NEVER seen two gauges the same, in fact. For one reason, you lose a little air each time you check. I wonder if the sensor device itself has a tiny leak.

Some of the tires have plastic caps, some not. I had a cap on this one originally, but I lost it a while back. No difference. I keep meaning to buy some of the metal ones with the core tool, but I forget.

Yes. The others hold air for months with or without cap.

I'm sure that if the dealer (amazingly enough, and against everything I knew about buying used cars for the last 50 years, I bought the car from the dealer, and it was the first one I drove when I decided on a 2- or

A *visual inspection in-situ* will not find a slow leak. All that is doing is a scan for the obvious, like a *visible nail*. To do a proper inspection for a slow leak, you really need to remove the wheel and do an immersion test. A pressure leak that loses ~10psi over a week will show as a bubble every now and then during the test. When I was a wee apprentice, we had a water vat purely for the purpose of leak testing tyres. The practice works.

FWIW, your tyres are getting to the point where I would call them *time expired* or, as they say, past their *use by date*. I have never had the issue of tyres time expired, they are typically worn out in 3 to 5 years. I'd clock up 33 k miles in 2 years, maximum 3, so I've never seen a tyre on any of my cars over 5 years old.

Works fine for motorcycle and bicycle tubes. Car tires, not so much. Easier to just pump the damn thing every couple of weeks. Know anything about the effects of Slime on pressure sensors?

So I've been told, but I've never had tires "expire" from anything not involving tread, puncture or -- and this I regard as criminal -- sidewall bubbles in the defective and obsolete tires the Cadillac (or maybe it was Ford, it was quite a while ago) dealer sold to my mom at a premium price and refused to replace, turning the problem over to Bridgestone. My Ducati's tires held air for at least 20 years in spite of visible crackling on the sidewalls. Probably more because I don't know when the previous owner bought them.

They don't get much wear at 3K miles/year.

Cruise down the freeway on a very hot day at 70mph+ and your mileage may vary.

It's not about holding air.

Visible cracking isn't the issue so much as the depth of the cracking. Signs of cracking, and the tyre lightening in colour, are signs that the tyre is *aging* and losing the chemicals that keep the rubber supple and protected from ozone attack. Tyres that are cracking are showing visible evidence that the rubber is hardening so grip will be negatively affected.

My wife's car does 5k miles per year. It is currently at 30 k miles and is 6 years old. When it reaches 10 years old, the tyres will be replaced as a set *regardless* of how worn the tread is. FWIW, I don't even run tyres down to the minimum *legal* tread depth since I'm not a fan of aqualplaning.

The tire pressure sensor is part of the valve stem. It may not let you inject the goo. But if it does it may goo up the sensor. Rock Auto $30-$45.

If it is a nail / screw it may be difficult to find. Could never visually find them on my cars. Always had to over pressure then soap bubble.

I'd say that's a bare minimum :-)

No visible cracking or color change. That's kind of amazing, given the SoCal air quality.

I've got a year to go, then. I'm amazed that the Corolla still feels 'new'.

Yeah but tyres do that as a matter of course. It's their job.

It is indeed. The ozone at ground level is what does a lot of the damage, then there's the heat, the sun does the rest. Do you keep it garaged when not in use? That will help preserve it - including the tyres.

Hey, it's a Toyota, did you expect different?

Nope, it sits outside 24/7. Passenger side is shaded. No idea what the former owner did with it.

I don't actually think about it being 9 years old. It's the newest car (age, not birth-year) I've ever owned. Other cars have had 'issues' but this tire thing is the only one the Corolla seems to have. The interior could be designed better (like TURN THE GODDAM SPEEDOMETER ETC. LIGHTS ON ALL THE TIME, not just when the headlights are on, and make the seat rise higher -- not everyone is six feet tall!) but I can live with it.