Slow tire pressure leak
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#2
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Probably the valve stem if you see no visual damage to the tire, or know you have not hit anything. You can remove the wheel/tire, and place it in a large bucket of water, bathtub, etc. Obviously if you see bubbles you've found your leak. That is what a tire store will do. They have a dunk tank for this purpose. If you have TPMS on your car those stems are screw in's, it could be as easy as tighting the valve stem. Be careful though, don't over torque. I do not know the torque personally. Maybe the dealer will give it to you... Good Luck
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Did you read my post to help you? Another thought is to take a glass of water and pour it over the stem. If it bubbles, you know it's leaking. You don't have to remove the wheel for that answer. You have also not said if you have regular stems or tire pressure monitoring stems, this makes a difference. You can tighten the tpms stem and probably stop the leak. A normal rubber stem will have to be replaced. Trying to help you out...
#7
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Knansas997, I have tried to spray soappy water to the valve steam, no bubble. I have the rugalur rubber valve steam without TPMS. Thank you for your input. Just want to find out whether this is a common issue prior to my oil service appt. next week, so I know how to talk to my service adviser.
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#8
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I ran into my first tire issue on Saturday--yesterday. After a morning of spirited driving I parked alongside a residential curb, and returned about 30 minutes later. The TPMS alert instantly came on and told me I was low on air,--Right Rear,--what I consider the most typical place for picking up a nail or something (in the left-hand-drive countries). The usual TP for that much driving was 43psi and it was hovering between 33 and 34. I decided to nurse it home. Got home, pulled that wheel off, and sure enough, a nice nail in the tread. It was tough to pull out! As soon as it came out the tire started losing air quickly. I used my radial tire repair kit to auger out the hole a little bit more, and then put one of those radial tire plugs onto the plugging tool and shoved it in, and then pulled it out halfway. Cut off the plug material at the surface of the tread. Broke out the compressor in the trunk (by now TP was at 21psi) and plugged it into the cig lighter. My friend said, "what will you use to measure the air pressure?" I said, "how about letting the car tell us." I turned on the ignition and the TPMS readout started at 21psi and finally at 34psi I stopped the compressor and pulled it off. I took the car out for a short drive (to settle ensure the plug was set) and monitored the TPMS the whole time. The real test was the overnight one. I went out to the car and turned on the ignition. TPMS told me the story. Both rears were sitting at 39psi. Leak fixed. With the sort of hole it is I have no fear of driving it on the road,--and I have total, no questions asked, tire replacement insurance.
As I mentioned in an earlier post, we should all ensure that we have a radial tire repair kit in our trunks. They're less than $10 and they give me a considerable peace of mind. I have to admit that it was a lot easier to do this in my friendly garage, and not at the side of a busy highway.
What you need:
Radial Tire Repair Kit (with auger and plugging tool and plugs)
A pair of duck nose or such pliers to pull out the violator
A razor blade to trim off the plug
Nice to haves in the garage:
Floor jack and jack plate for a 997
Torque wrench and 19mm socket (deep)
Wheel hanger(s) for the car
Lock socket for the one lug (from tool kit)
Pair of leather work gloves
Vial of soapy water for isolating the leak
As I mentioned in an earlier post, we should all ensure that we have a radial tire repair kit in our trunks. They're less than $10 and they give me a considerable peace of mind. I have to admit that it was a lot easier to do this in my friendly garage, and not at the side of a busy highway.
What you need:
Radial Tire Repair Kit (with auger and plugging tool and plugs)
A pair of duck nose or such pliers to pull out the violator
A razor blade to trim off the plug
Nice to haves in the garage:
Floor jack and jack plate for a 997
Torque wrench and 19mm socket (deep)
Wheel hanger(s) for the car
Lock socket for the one lug (from tool kit)
Pair of leather work gloves
Vial of soapy water for isolating the leak
Last edited by Edgy01; 12-04-2006 at 11:59 AM.
#9
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This won't completely help but it's a good tip for anyone. Go to Costco and fill your tires with Nitrogen, molecules are bigger so no slow leaks say over storage, when your beatin the snot out of the tires it resists expanding so your psi stays level ( Nitrogen is used in F1 &probably other racecars) and also it won't react/oxidize with the inside of your tires.
As for the slow leak, maybe the tire needs to be reseated? Bead damage? I'm not sure. Soapy water is your best bet as suggested or just live with the problem until you need new tires, in my opinion-that's what I'd do. Well...maybe I'd speed up the process and do some uhmmmmm
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Cheers
As for the slow leak, maybe the tire needs to be reseated? Bead damage? I'm not sure. Soapy water is your best bet as suggested or just live with the problem until you need new tires, in my opinion-that's what I'd do. Well...maybe I'd speed up the process and do some uhmmmmm
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Cheers
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Dan- Good post and good advice. I am assuming you are not going to leave that plug in your tire for the long run. At the very least everyone should understand that what you did is on the money but should be followed up with an internal patch, as long as the area is not on or near the sidewall of the tire. There is a proper way of prepping the inside of the tire as well to properly patch the tire. Your post almost sounded like you were going to replace your tire based on your road hazard insurance. Either way a plug is really a temp answer on a vehicle like a Porsche, with the rear weight, and the performance.
As far as Nitrogen goes I also agree with Dan. But I will say this... F1 teams do use Nitrogen for tire fills and even the cycling world has tinkered with nitrogen and even helium(sp?) as a alternative source of inflation...
Cleanme's right it could be anything, get it to your dealer or tire store in the morning. YOu could have picked up a nail like Dan and then thrown it back out creating a small hole closing in on itself. As a former owner of a wheel/tire store I have seen it all. Don't sacrifice yourself or your beautiful car for a proper discovery and fix...
As far as Nitrogen goes I also agree with Dan. But I will say this... F1 teams do use Nitrogen for tire fills and even the cycling world has tinkered with nitrogen and even helium(sp?) as a alternative source of inflation...
Cleanme's right it could be anything, get it to your dealer or tire store in the morning. YOu could have picked up a nail like Dan and then thrown it back out creating a small hole closing in on itself. As a former owner of a wheel/tire store I have seen it all. Don't sacrifice yourself or your beautiful car for a proper discovery and fix...
#12
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Hi,
I had a tire patched because of a nail. I would recommend the
plug for a temporary fix.
Formula one teams use nitrogen because it will not incrase
pressure the same as air due to heat. The tires should increse
about 2 psi from a spirited run.
Paul
I had a tire patched because of a nail. I would recommend the
plug for a temporary fix.
Formula one teams use nitrogen because it will not incrase
pressure the same as air due to heat. The tires should increse
about 2 psi from a spirited run.
Paul
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Originally Posted by Stephenkng
Dro, did you find out what happen
I will let you know if it is gone after I put the new tires on in a couple months.
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I drove around for several months with a slow leak until the dealer found a small screw in the tread that was barely visible. They (and a local tire store) refused to patch the tire even though it was nowhere near the sidewall.
Recently the dealer found a small nail in a tire and recommended replacement. Because my last tire replacement at the dealer cost $450 I declined preferring to take it to an independant shop instead. After doing that, the shop told me that I didn't need a tire replacement because they leak tested it and nail did not perforate the tire. Why the ******** at the dealer didn't leak test it is a mystery to me (well maybe not). It's been 6 weeks since this episode and the tire has required no addition of air.
FWIW there is a nationwide backorder on Conti SP 2 in 265/40-18 size (rear). This has been going on for several months. Never again will I accept a car with Continentals.
Recently the dealer found a small nail in a tire and recommended replacement. Because my last tire replacement at the dealer cost $450 I declined preferring to take it to an independant shop instead. After doing that, the shop told me that I didn't need a tire replacement because they leak tested it and nail did not perforate the tire. Why the ******** at the dealer didn't leak test it is a mystery to me (well maybe not). It's been 6 weeks since this episode and the tire has required no addition of air.
FWIW there is a nationwide backorder on Conti SP 2 in 265/40-18 size (rear). This has been going on for several months. Never again will I accept a car with Continentals.
#15
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Official "Porsche" policy is tire replacement and no tire repair. It's a liability issue. Period. Common sense dictates that if you aren't out there flogging the car everyday you should be fine with a plug or patch. Besides, at the rate we go through rear tires with these babies, you're not going to be driving on that plug for long! (See, there IS a happy tale in there).
Personally? I'm leaving the plug in, and I'm not worrying about it. In another 5000 miles it will be on a recycling pile somewhere.
Personally? I'm leaving the plug in, and I'm not worrying about it. In another 5000 miles it will be on a recycling pile somewhere.