tire losing air, but I can't find a leak

jwasbury · 08-31-2010, 01:54 AM

I'm having a strange issue with one of the tires on my '06 Mini. It has a leak, usually slow, but other times not so slow. Most of the time it can go a week or so...pump it up to 30psi and a week later its at 20psi. Sometimes, like this morning, I'll find it completely flat, when I only just filled it a day ago.

I yanked the tire, filled up with air, then submerged it in my bathtub. Can't see any signs of a leak. I also made up a soapy water solution and sponged the entire wheel with it and found no leaks. The tire picked up a nail once and its been plugged, which is naturally the first spot I checked, but it doesn't seem to be leaking there. I guess I'll replace the tire, but I just can't understand with these symptoms why I can't locate a leak.

Anyone ever experience something similar?

silverc4s · silverc4s's Garage

I had a similar situation on one of four new tires mounted on 15" Fuchs for me by Discount Tire. I took the offending tire/wheel back to them & they deflated it & remounted to the wheel & rebalanced, etc.
Problem solved.

MT930 · 08-31-2010, 08:12 AM

Check the inside rim for dings.
I had one that lost air only when the car was driven, yanked the wheel and found the ding that was affecting the seal. I was really scratching my head until I pulled the wheel.

Rot 911 · 08-31-2010, 08:17 AM

I had a similar situation, only mine was a constant loss of about 5lbs per day. Turns out I had a crack in the combination valve stem/tire pressure sensor. Tire shop found it and showed it to me.

porsche4life · porsche4life's Garage

Valve stem or bead leak....

slakjaw · 08-31-2010, 10:01 AM

Prolly a bead leak. You might have to put like 60 or more punds in it to actually find it.

crb07 · crb07's Garage

If it is a rubber valve stem push/bend it, you may here it start leaking.

cgarr · cgarr's Garage

Quote:

Originally Posted by crb07

If it is a rubber valve stem push/bend it, you may here it start leaking.

Had that happen and it only leaked when drive at speed, the stem would bend, then leak. Stop it was fine.

targa911S · 09-01-2010, 09:11 AM

The salt on the roads here pitted the bead rim on my wifes PT cruisers aluminum wheels.. Had to take the tires off and sand them smooth again to fix the problem. BIG PITA!

carreraken · carreraken's Garage

Had bead leak on my 'yota resulting from a poorly chromed wheel - the chrome was deteriorating along the bead... had to use bead sealer to stop the leak...

GDNF2ET · 09-01-2010, 11:24 AM

I had a similar issue with a 4runner I had..It would loose 15 - 20 pds in 2 weeks..Had the tire off and checked a couple times by different shops, till one day a shop figured it out..There way a very small leak within the rim..When the aluminum rim was forged, it musta had a pit or flaw in the metal..Small bubbles could be seen when submerged in water at the middle of the rim....

Brando · Brando's Garage

Quote:

Originally Posted by porsche4life

valve stem or bead leak....

+1

Por_sha911 · Por_sha911's Garage

Bead leak. Maybe it leaks more when the wheel is in a certain position. Either that or a neighbor is have fun with you by letting air out at night?

kanadary · 09-02-2010, 04:47 AM

sometimes its the valve itself if its not screwed on tight or you just got a bad one or one that is sticking when you put air in it. but i suspect you've checked that first.

tchanson · 09-02-2010, 07:44 AM

Quote:

Originally Posted by kanadary

sometimes its the valve itself if its not screwed on tight or you just got a bad one or one that is sticking when you put air in it. but i suspect you've checked that first.

Agreed. If you haven't done so, the first thing to do would be to make sure the stem is tight using an adjustment tool.

Tim