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When temperatures get low (this morning it was 12F), I wake up in the morning to at least one, usually two flat tires. Even in the summer, I have to put air in the tires every month. I've taken the car to the dealership and various places around Cincinnati OH. No one can explain it. their is no damage to the tires, no leaks they could detect, nothing. I drive a Pure with the standard factory wheels and it only has 13,000 miles on it. Does anyone else have this problem?
 

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Not monthly, but few times in the Fall and Spring. There isn't much air in those wheels, any major change in ambient temperature has consequences.
But it shouldn't be monthly. Unless either there is a leak or you're extra picky about minimal changes, changes that don't trigger the TPMS. :wink:
 

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I have found this as well. After getting the tires checked several times I find I had a bent rim, on the inside, and could not see the damage. The tire shop put some type of bead sealer on it and since then no problems.
 

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Not normal to have tires go completely flat without the TPMS going off if it is a slow leak. maybe the valve is hitting against a curb? It has happened to me, If they are putting the tire in a water tank to check for leaks, they ay have to add some extra air before a slow leak will show.

Tires will loose air over time but it usually takes more than a month.
 

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Usually it the TPMS that the problem... Tighten your valve cores & retorque the TPMS stems to proper torque... Also Discount Tire Store sells reseal kits for our smart sensors...

Note: You should always: refer to manufacturer's specifications for proper torque requirements when replacing nuts and valve cores; use new grommets, nuts, plastic or nickel-plated valve caps and electro-less, nickel-plated valve cores when performing any tire service; never use a brass valve core or un-plated brass cap with an aluminium TPMS sensor stem. Contact between dissimilar metals can cause galvanic corrosion, which can lead to loss of air pressure.
Note: You should avoid the use of any liquid or tire sealant injected into tires equipped with TPMS as this may block the pressure port and cause malfunction. If evidence of the use of tire sealant is noted upon dismounting the tire, it is also very important to remove all residual sealant from the inside of the tire and rim surfaces prior to re-installing the tire.

Of course there is the old stand by of putting the tire in the Bathtub...
 

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Discussion Starter #6
Thanks fo all the imput. my TPMS does go off every time the tires are low or flat, i check the pressure everytime it does go off to be sure that it is not malfunctioning. but when its super cold like this whole week, i fill the tires at 8pm and by 7am the next morning, they are completely flat. the problem has been primarily with the same two tires, the driverside front and back. I'm thinking that I have some bad rims, though the mechanics say they are fine. Thinking about trading up for steel and replacing all the tires with a larger size, maybe 185/55/15 on all four corners. or at least just getting the valve stems checked and two new standard rims
 

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If the problem comes and goes with overnight temp changes then my first guess is the seal between the tire stem and rim.
 

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I've had the same issue since the cold weather came - front tires have correct pressure, rears show 29. Pumped them back up, so far so good.
 

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This flat tire thing is driving me crazy. They say they have it fixed and two days later its flat again. This is my second winter with my Smart Car. Last winter had the problem, but the dealer got me a new tire and had no further problem, til this winter cold again.
 

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I find that I have tires loosing air during our cold winters here (15 to 17) and I have to inflate fairly often. My TPMS does trigger and let me know there is a low tire, but when I check them I usually find they are all low. I have never had this problem with any other vehicle, and I find it rather frustrating.
 

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I find that I have tires loosing air during our cold winters here (15 to 17) and I have to inflate fairly often. My TPMS does trigger and let me know there is a low tire, but when I check them I usually find they are all low. I have never had this problem with any other vehicle, and I find it rather frustrating.
I wonder if the stock tires/rims are to blame. :confused: I might add a pound or two once every three months or so on my aftermarket setup. Usually, I have to change the pressure anyway when I rotate the tires.
 

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I have wondered the same thing, if it is the stock wheels. I am getting ready to change mine out for some aftermarket wheels and it will be interesting to see if this problem goes away or is diminshed.
 

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You need to make sure the installation Nut is tight, and the Valve Core is tight... Also soap them up afterwards to check for leaks... A tires Rubber is porous... Its not uncommon that a tire to lose 1 pound air per month... After tightening the nut and core, and still losing excessive air per month, it is advisible to take the tire off, and put it in the bathtub to look for leaks...

 

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While a tire will loose 1 lb. of inflation pressure for each 10 degree drop in temp., what you are experiencing is far from normal. You have been given several possible leak sources in previous posts. Arm yourself with this list and re-visit the dealer. If possible, leave the car overnight when you know the temp. will drop significantly over night so they can experience the problem first hand. It could be that with the extreme night time temp. drop a crack or some other source of leakage is opening, allowing air to escape.
 
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