Turbo6TA

2011 GS Coupe

My left rear tire has been leaking down about 2 psi every 3 days.

I thought there was a nail or a screw in the tire, so today I jacked up the rear of the car so I could get underneath there and rotate the wheel/tire to get a good look ... Did not see anything wrong.

Well, it's leaking air, so there obviously is something wrong.

Next I filled an empty spray bottle with soapy water and sprayed down the tire to include the bead area on both sides. No bubbles at all from the soapy water.

Lastely I sprayed down the air valve. Sure enough ... there was bubbleing indicating a leak around where the metal part of the valve stem goes into the wheel.

As most of you already know, the air valve stem is actually part of the TPMS sensor. I tightened the 11mm nut on the TPMS stem, and no more bubbles!

Now, I will fill the tire back up to 30 psi and check it again later to make sure it hasn't leaked down.

I think I am going back out in the garage and give the rest of the TPMS valve stem nuts a little lightening too just to make sure there not going to leak any time soon.

Anyway ... That is my "tip" for the day

FYI ... Can't blame GM for this. As soon as I got the car, I changed the OEM tires, wheels and TPMS sensors for new Nitto tires, OEM Spider wheels and new TPMS sensors ... Local tire shop did the job.

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crusher1

Good job

FloridaGrandSport

My 2010 did the same thing in a couple tires. Tightened the nuts and no more air loss.

Zoxxo

Another thing to check before you dismantle everything is the valve stem cap. Many of them contain "rubber" washers which can come unseated and, when you tighten the cap down, can exert a small pressure on the valve stem needle. Instant slow leak...

Z//

Corby

Good tips, gonna check mine.

Bobbyosto

Have this same issue on my Camaro; don't think the stems have nuts. Will check it out.

Kdurgin

62 inch pounds is the correct torque. That is just over 5 foot pounds which isn't much.

C8-Vette

I check the torque on mine at least once every 6 months. I believe about 60 inch lbs, thats inch pounds not foot lbs.

richp5

Thanks for the tip. I have to fill one tire every ten days or so and it was a little loose. Hope it solves the problem!

1FASTVERT

I have that happen before but today it was a nail in the side wall of the right rear tire. Damn the bad luck!!!!!!

LucaBrasiAZ

great post...my passenger rear has been losing about 3psi per week...figured the same as you with a nail somewhere on the tire. Hopefully you described the same issue im having, i would be a very happy camper!

PeterSG

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This is obscure situation is worth remembering. It happened to me just days ago. One of those little o-rings jammed against the valve core and caused a tire to go totally flat.

BIG Dave

Wow! I've been dealing with this same problem for months! Right rear. No sign of a nail. I'm going to go check the nut on the TPMS stem. Thank you!

LucaBrasiAZ

i tightened mine up over the weekend and guess what, right passenger side is no longer losing air! Thanks for the great tip!

actually lightly tightened all of mine...the other 3 would only go 1/4 turn ( didn't want to go super tight so i left it on the snug side) but the passenger rear went 3 total turns.

mundo

Good tip. Mine does it too. I'll check the valve stem nut.

Turbo6TA

Got that right!

Could you imagine trying to tighten that little #11mm nut to 60 Ft Lbs of torque. That just a little less than the head bolts!

I don't even bother with a little torque wrench on that nut ... Just snug it down good without over tightening the little thing.

Batman 357

I've got a slow leak in the LR. I'll check that. Good tip......

chasboland

This actually solved my slow RF leak of 2# per week. Be careful though, just tighten it only a very small amount.

C8-Vette

Been on this forum for almost 7 years. Members knowledge range from individuals who can install their own cam to others who would have trouble changing their battery. Got to be specific when giving technical info.

Turbo6TA

I guess your right