Slow tire leak? Help!

"macanamera" (macanamera)
06/10/2014 at 08:55 • Filed to: None

Alright so my back left tire loses pressure extremely slowly, and by that I mean 1-2 psi a week, maybe. If I drive it every day, it loses less air than if I let it sit. I have dunked the wheel, no bubbles, the rim is flawless, there is no puncture in the tire that is visible to the human eye.

What do I do? Again, I have already taken the wheel off and inspected it (well), dunked it in soapy water, etc etc. Please advise.

DISCUSSION (31)

yamahog > macanamera
06/10/2014 at 08:56

Valve stem? I suspect the same on my front motorcycle tire right now as well.

crowmolly > macanamera
06/10/2014 at 08:56

Filled with air or nitrogen?

Mattbob > macanamera
06/10/2014 at 08:58

you probably need the special air they fill it up with at the tire place. But really, probably what Yamahog said, valve stem. How long did you leave it under for when you dunked it? A slow leak would take a long time to build up a bubble.

Arch Duke Maxyenko, Shit Talk Extraordinaire > yamahog
06/10/2014 at 09:00

This ^^^

Try taping it up with black electrical tape and see if it helps, if the leak stops, you know your problem.

macanamera > crowmolly
06/10/2014 at 09:00

Nitrogen, but I can't imagine that make a difference. Air is 78% nitrogen anyhow.

FrederickLawOlmsteez > macanamera
06/10/2014 at 09:01

Kinja'd!!!

I think the car is using the extra pressure to froth the milk for your cappuccino. Try getting espresso (no milk) tomorrow and see if that makes a difference.

macanamera > Mattbob
06/10/2014 at 09:02

5 mins? Maybe a little more?

macanamera > Arch Duke Maxyenko, Shit Talk Extraordinaire
06/10/2014 at 09:03

Taping what, though?

Arch Duke Maxyenko, Shit Talk Extraordinaire > macanamera
06/10/2014 at 09:06

the valve stem

macanamera > FrederickLawOlmsteez
06/10/2014 at 09:09

Since I only drink certified organic fair trade coffee grown in volcanic soil, brewed using the traditional pour-over method in a Japanese carafe, I can't see how that would be the problem.

macanamera > Arch Duke Maxyenko, Shit Talk Extraordinaire
06/10/2014 at 09:23

But where? My valve stem is metal:

Kinja'd!!!

macanamera > yamahog
06/10/2014 at 09:24

My valve stem is metal, where would it leak from?

Kinja'd!!!

davesaddiction @ opposite-lock.com > macanamera
06/10/2014 at 09:29

My guess is also valve stem. Have you aired it up to the max pressure the tire is rated for and checked it for leaks then?

yamahog > macanamera
06/10/2014 at 09:30

I don't have any experience with metal valve stems, but if there's any corrosion at the base, that could be it. Can you have a tire place check it?

davesaddiction @ opposite-lock.com > macanamera
06/10/2014 at 09:31

So, what is that icon for? Will it warn you if it thinks you're getting tired?

macanamera > davesaddiction @ opposite-lock.com
06/10/2014 at 09:31

Oh, that's a good idea! But the valve stem is metal, so I don't know where it would be leaking from really.

davesaddiction @ opposite-lock.com > macanamera
06/10/2014 at 09:39

It might just be a defective part. Can you tighten that little nut?

At a track day last year, I lost pressure in a tire while out on course (not fun). I took it in to the race shop, they checked the tire and couldn't find anything. I went out for another session, and the same thing happened. They aired it up very high and finally found that it was a bad valve stem.

macanamera > davesaddiction @ opposite-lock.com
06/10/2014 at 09:42

That's what they say, although I have to admit I have never seen it warn me, or if it has, I haven't noticed the warning. Maybe I have never been tired? I doubt that though. I'm not entirely sure how it works. It's also a little creepy, because if I remember the literature correctly, the car measures like 50 different parameters about you at all times...I think it's called Attention Assist TronicMatic Plus.

Edit:

An industry first, ATTENTION ASSIST takes note of over 70 parameters in the first minutes of a drive to get to know your unique driving style. As your journey continues, it can detect certain steering corrections that suggest the onset of drowsiness. It then considers a wide array of other factors, from crosswinds and road smoothness to how often you're interacting with the vehicle's controls and switches. If it all adds up to driver fatigue, ATTENTION ASSIST sounds an alert encouraging you to stop for a rest

Textured Soy Protein > macanamera
06/10/2014 at 09:43

Yeah the valve stem is metal, but it's got a valve in it. If for some reason the valve isn't staying perfectly shut 100% of the time, it could be letting air seep out in little bits.

My gf used to have a Nissan Sentra where the valve stems with integrated tire pressure sensor would get corroded on the inside (battery leaking or something? I don't really know) and leak air. We'd take the car to the tire shop where they'd diagnose the problem as a corroded valve stem, and just like clean it off with a wire brush and magically the tire holds air again.

davesaddiction @ opposite-lock.com > macanamera
06/10/2014 at 09:47

Sounds like you haven't yet been tired enough behind the wheel to be considered dangerous. Pretty cool tech, even if the name isn't. Both my parents have fallen asleep at the wheel before (my dad rubbed up against a semi's tire and my mom woke up in a grass median), so I'm pretty cautious about going any further once I sense fatigue setting in...

macanamera > davesaddiction @ opposite-lock.com
06/10/2014 at 09:56

Whoa, I hope they were ok!

davesaddiction @ opposite-lock.com > macanamera
06/10/2014 at 09:59

Yeah, somehow they both were fine, thank goodness. The tire mark on my Dad's car was pretty crazy to see. My mom woke up in the median WITH THE CRUISE ON! Needless to say, that's the first thing I turn off when I start feeling tired.

You can tell a Finn but you can't tell him much > macanamera
06/10/2014 at 10:05

The valve stem has some type of rubber seal between the metal and the rim. Soap the valve stem and give it a few minutes to see if you get bubbles. If it is a slow enough leak it might take a few minutes and it might foam as opposed to making bubbles. I currently have a very slow leak that is coming from my valve stem I need to get fixed.

macanamera > davesaddiction @ opposite-lock.com
06/10/2014 at 10:09

Yikes! That's scary.

macanamera > You can tell a Finn but you can't tell him much
06/10/2014 at 10:10

Thanks, I'll give it a shot.