Tire Pressure - Noob Question
 

Sorry if it's a dumb question but I'm quite a noob when it comes to car stuff.

To begin I'll provide some details on my car.

2010 Mazda 6
27000km
Recommended PSI = 30 (Set to 30 b/c I only drive City)
Last Serviced a month ago

So 2 weeks after my last service the low tire pressure came on. I checked the PSI on all 4 tires and 3 of them were at 30 and one of them was at 24.5. I topped it up to 30 and the light came off. Started driving it and all seemed fine for a while and the light didn't come back on so I thought nothing of it. So last night (2 weeks after I topped it up) the light came back on. PSI is at 24.5 again. Now b/c this is a tire we're talking about I should probably be concerned. Anyone experience this before? I guess it would be best to bring it to a shop asap I suppose. Like I said, I know this is probably a dumb ass question but I'm a noob :okay:

Is it the same tire that is deflating? And are you using a regular tire pressure gauge or a digital one?

Yes same tire and using a digital pressure gauge.

Assuming it is the same tire, it sounds to me like you have a slow leak somewhere. The likely culprits are somewhere on the tire (rubber) portion, or the valve stem. Somewhat less likely is that your wheel isn't holding air as well as it should.

If you have a big enough tub of some sort, I would take the whole tire in under water and see if there are any air bubbles forming / coming out. Failing that, pour soapy water over the various places on the tire, one section at a time. Look for bubbles forming and listen for any hissing / air leaking noise.

Failing that, I'm sure someone more knowledgeable than me would be able to offer other suggestions as well.

Take a quick visual inspection and check if you have a nail, most likely you do and will need to bring it into a shop that does tire repairs.

Not to threadjack, but is there a difference between analog and digital gauges, apart from the obvious?

Sounds like a slow leak. It's good you caught it early... Check for nails or hissing air.

Thanks for the responses so far. I know the obvious would have been well duh go get it checked for a leak but I appreciate input so far. Let's assume there's a nail or small puncture of some sort, is this typically something that's fixable? If so how much is a tire repair like this usually cost you? Any recommendations to what place to go?

Its fixable if you catch it early. You can have it plugged/patched.

This happened to me once before but the puncture was too big and by the time I realized it the sidewall was damaged beyond repair.

Yes, it's fixable, assuming the nail didn't puncture the sidewall.

I took mine a few weeks ago to the guys at The Speed Syndicate. I went there and they took care of me. I believe it was $25+ HST ($28.) I got lucky. If I had run on my tire any longer, I would have either totalled my car or I would have had to buy an entire new tire. They plugged it up for me and so far, so good! :D

The Speed Syndicate guys are awesome, but I've also had very good luck with Kal Tire. If it's just a patch/plug job, sometimes they'll do it for free if you go when they're not busy.

They did that for me 3 times, different guys, not hook-ups, etc.

So brought it to JRS Auto today and confirmed it was a nail. $10 and was dealt with pretty quickly. Just glad it's all over lol

For $10, I assume it was a plug repair?

Actually I have no idea, I just know he said it's $10 b/c they didn't have to take off the tire but it would have been $18 if they needed to. It's my friends uncle and my whole family has gone to him for years so I trust whatever they did was fine.

Curiosity though what's the biggest difference between patch vs plug?

Plug is like it says, they put something in the hole and slap some tar (or something close to) to seal the hole from the outside. That's why there's no need to remove the tire from the wheel.

A patch is placed on the inside of the tire where the hole is, and patches the area. With the air pressure pushing against the patch. You need to remove the tire for this.

Better places (such as Kal tire) use a plug & patch, which is a patch that has a plug together - sort of a hybrid.

^^
Thanks, I guess the name of plug or patch was obvious but that does give me a better idea. I like the sound of the hybrid but oh wells I would assume since both plug or patch has been methods that have been used and are still being used to this day so it shouldn't be too much of an issue.

It usually depends. Chances are you won't have trouble, but plugs are very visible from the outside. and sometimes they do fall out, so remember to keep watch on your tires...but you should be doing that anyway =p

I've experienced that plugs from the outside in are not as reliable as a plug and patch from the inside out. Like what inv4zn says, keep an eye on it in case it wears out, and try getting them to patch it from the inside if it does. I work at a tire shop and we do all repairs from the inside regardless of what the puncture is, and all our customers never come back for a second repair :thumbs:

So all Kal Tires fix flats for free???

I've had two vehicles with flat tires fixed for free at the North Langley/Port Kells Kal Tire.

They did patch repair both times. Patch is the best as they glue that sucker to the inside of the tire. Since you have pressure inside the tire, it ain't going anywhere, whereas a plug can come out. Mind you, done properly, plugs should be ok.

As for digital tire gauges, it's just easier to read. Some light up to make reading pressure at night easier. There are acurate ones on both sides as well as sucky ones. Digital ones run on batteries, while analog....... you get the idea. I like dial gauges better than the stick gauges. Oh yeah, digital ones can give you reading in tenths or hundredths of whatever scale you use, although if the gauge is inacurate to begin with, there's no point in it............. just rambling.

One more......... Not a standalone tire gauge, but I love my Milton tire gauge/inflator. Love the magnifying bubble lens.... oldie but goodie

http://www.amazon.com/Milton-Dual-Chuck-Inflator-Gauge/dp/B000BMIQ4O

I think it's just a service they provide - it certainly brings back customers.

Some auto-glass repair shops do this as well. My dad went in to fix a stone-chip and they did it for free. Now our entire family goes back there everytime.

I've been questioning your very point, what if tire-gauges are inaccurate to begin with? I'm sure some of the cheaper ones are duds, and that means I'm rolling on 4 underinflated tires, while thinking they are properly inflated. Doesn't mean i can buy 4 to make sure they're consistent either.

Yeah initially the first flat repair as a first-time customer is on the house as a courtesy thing, but hopefully that will bring you back again for future visits in the case that you want other chassis-type work done with us in the future. We always use plug/patch combos for any flat repair; for large punctures we use a separate patches and plugs.

winson, I suggest you bump your pressure up to 32psi. You should notice better handling and fuel economy by doing so.

I wouldn't worry too much about the plug either, especially since you have tpms to warn you.

I only use combination patches (patch/plug) on my cars, just for piece of mind. Then again, it doesn't hurt that I have a tire machine :troll:

Werd, I actually bumped it up to 32psi recently :fuckyea: