lldknyll26

i noticed my psi on my rear right tire is decreasing gradually. From 37 it went down to 34 within 2 month period. So i decided to put more air raising the psi to 39. So 3 month later, the psi is at 35 while the other tire's psi remain the same. Something wrong with my tire? Leaking air perhaps? Should i bring it to the dealer and have them check it out or go to a tire shop and see if the airs leaking?

stock to the bone

mine is the same except the leaking tire is the rear left. Mine leaks faster than yours.

csmeance

air leaking out over the course of weeks is perfectly fine as rubber in tires is not completely air tight! Some air will escape from the tire, just as air escapes from balloons. Don't over inflate your tire's to 39 PSI, keep them at 35 PSI COLD and just check monthly to make sure they are + or - 2 PSI>

lldknyll26

but why is the psi decreasing now? why not from the start? its been exactly 2 yrs since i had purchased the car and it was fine up until now. perhaps the tire is getting old?

csmeance

it is possible, rubber ages just like everything else and oxidizes...

Cyberdemon

First off thats too much pressure. If you look at the placard on the drivers side door the regular TL (at least my Type S) is 35PSI front, 32psi rear. Over inflating a tire can cause it to bulge which causes uneven wear. The front tires naturally get more pressure because the car is heavier at the front than the rear and they need to support more load.

A gradual decrease isn't anything to worry about. Air not only expands and contracts based on the air temperature, but different conditions of the rubber and the seal on the rim will all impact it's ability to hold air. If it dropped 10PSI in a day - you would have an issue. 3 PSI in 2 months is negligible, and it is potentially dropping more rapidly because you have more air then the tires like. It can also be a microscopic leak, or just an uneven seat on the rim. Occasionally even something like a pothole will cause some flex in the tire and if dirt starts to get stuck between the bead and the rim, it creates an opportunity for some airto escape. You could take it to a shop, have them pull it off and reseal it but for that amount of pressure loss it is completely pointless. They'll probably do more harm then good because then they need to rebalance the wheel.

The beauty of having a car with TPMS is it takes all of 3 seconds to check your air pressure. Just check it periodically and keep an eye on it. You usually want to adjust your pressure once a month anyways to account for seasonal changes in temperature. As the roads warm up your tires will start to heat up much quicker so you definately want to make sure you aren't running almost 40psi cold - at that point you risk a blowout once it starts to heat up.

Turbonut

iTrader: (1)

Pump it up to 50 and place it in water, or have a shop do the job. An object could be in the tire, or the TPMS sensor could be leaking at the seal or valve.

lldknyll26

TPMS sensor could leak at the seal or valve? if thats the case then i have to bring it to the dealer. would that be covered under warranty? What is the correct psi level at this time of the year where the temp ranges from some where btwn 70-80 degrees. I do fully understand that the tire psi fluctuates due to the temperature but losing psi just on one tire seems somewhat fishy.

EvoToTL

iTrader: (6)

also make sure the strader valve isnt loose

lldknyll26

and how would i know if the valve isnt loose? from the dealer?

Turbonut

iTrader: (1)

When you put it in water you'll see the small bubbles appear where the leak is located. If it is the valve stem, it just needs to be tightened, although I have seen some that won't seat and need to be replaced. Same as the sensor, they can leak if not tightened properly, or can leak if the seal is fractured.

Need to find the leak before attempting the repair. Any tire shop should be able to help.

I hate cars

That's too much air in too short of a time. As it was mentioned, it's leaking from somewhere.

39psi is on the high side for stock tires but for some aftermarket tires it's fine. I run mine at 40psi all around.

My tires show a variance from cold to hot but I only add a little in winter and let some out in the summer. They don't leak a measurable amount of air over a 6 month period.

Turbonut

iTrader: (1)

Opne of my other cars has a TPMS and I can't remember the last time any needed air although I do a physical check every now and then, just to make certain they are the PSI I want.

Cyberdemon

If it concerns you enough just take it in to either the dealer or a tire store and they can inspect it and find where it's leaking.

I deal with the same thing on one of my tires (~1psi loss a month) but I'd rather not have some underpaid tire goon scratch up my wheel with an impact gun, have to pull off and rebalance my wheel, and pay the ~$20-40 (probably more if it's a dealer) for them to fix when I could just pump it up every few months in my garage for free.

I hate cars

I do agree with you there. Everytime my tires are unmounted and mounted there's a new scratch. I have the urge to remove my own wheel weights ahead of time so they don't get scratched from removal. I did mounting and balancing when I was young and it's not hard to not scratch the rim, it's just a lack of caring and pride in the job.

Cyberdemon

I can not tell you how much crap I have dealt with from a multitude of shops on different cars.

-Tires mounted backwards (tech got pissed at me when I told him to fix it because "it was so hard to put on the tire" and it was after 5:00)

-Rims scratched around lug holes

-Rims STOLEN off my car when left overnight

-Lug nuts/wheel locks cross threaded

Admittedly my Acura dealer hasn't scorned me yet but I've only brought the car in once for warranty work. If I can do it myself I'm not going to leave it up to someone who cares nothing about my car to do it.

smarty666

That was God's way of telling you that you have too much air pressure in your tires. I can imagine how choppy and rough the ride must be in your TL with that kind of cold pressure in the tires.

The recommended pressures are 33 Fronts/ 32 Rears; I usually do 34 Fronts/33 Rears in spring and summer with 35 Fronts/34 Rears in winter. I wouldn't put any more than 36 PSI in cold!

lldknyll26

The manuals says the front should be 35 and the rear should be 32, 3psi diff. The tech from acura dealer told me that the front doesnt have to have more psi than the rear. He claims its best to have all four tires with 33 or 34 psi. When i had first purchased the car, the car came with 48 psi in the front and 45 in the rear. It even went as high as 52 psi.

I hate cars

Yep, once you go with aftermaket tires, the door placard is no longer valid. It's ok for getting an idea of the percent difference front to rear.

I run mine at 38-39 in all 4 right now. There are many things that affect handling balance. I try and tune it with swaybar settings and then tire pressure to fine tune it. Luckily the car seems very neutral with all 4 the same. Of course, under track conditions, the fronts seem to rise in temp more than the rears so you have to compensate for that by dropping cold pressure in the fronts by a few psi.

I hate cars

I've been there before. It's amazing how many things they can mess up on such a simple job. I tell them no impact guns, even with the torque bar. The torque bar is pretty accurate but using an impact socket with a free spinning speed of 6,000rpm scratches the rims pretty quickly around the lug nut holes. Besides, those speeds tend to gall threads easily. They always get annoyed but I don't care.

I have to lol about that "after 5:00" comment. They risk a potential serious hazard in the rain with the tire spinning backwards to save some time. Amazing but not surprising.

mglax13

iTrader: (3)

I had a similar problem and the seals around the TPMS were leaking. Tightening it didn't help, so they just swapped out all the parts with fresh ones from a TPMS rebuild kit and now it's A-OK.

I had the local Firestone do it. I could have probably taken it to the dealer, but it's actually easier to just drop in and pay someone the $25 that it cost me, than it is to make an appointment with the dealer, then go there, sit there for like an hour, have them tell me they need to perform all sorts of other service that I deny, then treat me like overall sh*t because I'm only having warranty work done.

stillhere153

iTrader: (1)

precisely what I was going to suggest
http://cgi.ebay.com/ebaymotors/NEW-T...Q5fAccessories

Turbonut

iTrader: (1)

Got to find the leak first, as it may not be the TPMS seal.

stillhere153

iTrader: (1)

well the guys did mention above the best way to find the leak is to submerge it and rotate it slowly looking for bubbles... last week (thursday) my tpms (!) light came on, I checked psi on all 4, pass rear side was at 29psi... I topped it off and saturday tpms (!) came back on, so I dropped by a tire shop and sure enough nail in the tread...

Turbonut

iTrader: (1)

If you wan to try it yourself, have the valve stem on the bottom and spray with some water, if it's leaking you can see the small bubbles, and if not, jack up the car to get the tire off the ground and turn the tire slowly while looking for and object in the tread. Most times it can be found/seen, but if a very small object, it will need to be placed in water.

nfnsquared

Yes, if by aftermarket, you mean tires that differ from OEM recommended size. OEM recommended tire pressures still apply if using OEM recommended tire size/type.

rromero

I check mines at least once a month just because you go from hot to cold every day, specially if it is your daily.

phred

Since this comes up a lot ... on the sidewall of every tire is a MAX PRESSURE number. That's a number you must not exceed. Anything short of that, knock yourself out - set the pressures wherever you want. The number on the door placard is a recommendation from Acura based on a combination of comfort, handling and fuel economy. Most sporty drivers take it up a notch or two.

Also, because it's considered safer to have a car understeer, manufacturers tend to come up with numbers that will encourage that. So again, if you want to take the fronts down and the rears up, have at it. Just realize it might make your pressure sensors very unhappy. Once you're the driver/owner, you can adjust pressures however you want.

FWIW, I had a tire that kept dropping pressure and I didn't monkey around, I had to have some work done so I had them look at it. Screw in the tire. The pressure monitor wasn't lying.

I hate cars

You can have the same size and have vastly different ideal pressures. You can have different sizes and have the same ideal pressures. There's more to tire construction than size and type. OEM recommended pressure only applies to OEM tires and that's only if you're using the car as the OEM intended (going from point A to point B in comfort).

In general, I agree, more often than not, wider tires on the same width rim will require slightly more pressure but not always.

In all honesty, my NT05s stick like glue up to 41psi and then they give up. I ran the stock tires at that pressure for a short time and didn't notice much difference. I had to run more in the fronts than the rear for decent balance. Now with all of the suspension work and different tires it handles best with all 4 at the same pressure (hot). I took it out and chalked the tires and rolled it until I got the flattest foot print. Later tests confirmed I was in the ballpark for best handling.

Many members are running aftermarket suspension. Just installing a larger rear swaybar throws the factory recommendations (from a performance point of view) right out the window. The car is now more prone to oversteer, handling balance has been changed, OEM recommendations do not apply except for comfort.

nfnsquared

I'll let NHTSA speak for me:

Understanding Tire Pressure and Load Limits

Tire inflation pressure is the level of air in the tire that provides it with load-carrying capacity and affects the overall performance of the vehicle. The tire inflation pressure is a number that indicates the amount of air pressure– measured in pounds per square inch (psi)–a tire requires to be properly inflated. (You will also find this number on the vehicle information placard expressed in kilopascals (kPa), which is the metric measure used internationally.)

Manufacturers of passenger vehicles and light trucks determine this number based on the vehicle's design load limit, that is, the greatest amount of weight a vehicle can safely carry and the vehicle's tire size.The proper tire pressure for your vehicle is referred to as the "recommended cold inflation pressure." (As you will read below, it is difficult to obtain the recommended tire pressure if your tires are not cold.)

Because tires are designed to be used on more than one type of vehicle, tire manufacturers list the "maximum permissible inflation pressure" on the tire sidewall. This number is the greatest amount of air pressure that should ever be put in the tire under normal driving conditions."

Tire Size

To maintain tire safety, purchase new tires that are the same size as the vehicle's original tires or another size recommended by the manufacturer.

http://www.nhtsa.gov/cars/rules/tiresafety/ridesonit/brochure.html

Would love to see references that back up your statements....

I hate cars

My references are common sense and a lifetime of doing this. What I state is also considered common knowledge in the automotive world, but apparently not around here. I'm not an internet dork that needs quotes to back myself, I've done it in real life.


This has no substance at all, it's as vague as vague can be, I shouldn't even have to explain this and it in no way backs up your earlier statements. You're just not understanding it fully.

You fell for that lawyer crap hook line and sinker. Of course they are going to recommend you run the same size as stock. Do you really think running a wider tire poses any sort of safety issue? I hope not. Things like lawsuits from uneducated people and CAFE standards come to mind when reading that.

Now, once again, try and understand this....

Once you change the suspension, you just threw these recommendations out the window from a performance point of view.

Once you change the brand, chances are the factory recommendations are no good.

You're completely overlooking the fact that different tires have different load ratings that require a different working pressure.

If your goal is better handling, the numbers change. If it's better mpg, the numbers change. If it's better comfort, the numbers change. The placard is what the factory considers the best compromise over a broad spectrum of factors.

Conclusion: While size does matter, there are many other factors in determining ideal pressure. You can't just focus on one area.



While we're at it, explain why only a 235/45/17 and a 235/40/18 (aspec) are the only tires you can run on a TL. This should be fun. Oh, and tell the guys that have aftermarket rims and tires that they're a serious risk to our safety lol.

nfnsquared

I didn't think you could support your statements. You have now confirmed it.

I hate cars

You're a sad little person. Do some more research, on the internet of course, I wouldn't expect you to get in the car and try different things like I have, then come back and thank me for teaching you. My statements are fully supported, you just haven't done the research required and I'm not a babysitter.

You see, this is the problem with people like you. You don't know enough to know that you don't know enough.

nfnsquared

Yeah, I knew it wouldn't be long until you started your name calling again....you're so predictable...you cannot seem to enter into a discussion/argument/disagreement without starting your name calling. You've done it countless times here on Azine and have been banned for it. Here you go again....

I hate cars

Shot number one.

Shot number 2.

You've got to expect some retaliation here. Show me where I called you a name. I think you need some time away from the computer because you're imagining things.

This is not a discussion from you, it's a calling out, don't act like you're innocent. You purposely provoke me and then step back and play the victim.

You have not answered a single question, you just try and prove me wrong every chance you get and I'm not talking about just this thread. You know exactly which ones I'm talking about.

Guys like you just repeat what they find on the internet without knowing why they're saying what they're saying or the meaning behind it. I'm sorry you disagree with me but I'm not going to believe your out of context quotes written by a lawyer over my own eyes and first hand experience at the track and on the street.

Again, do more research or better yet, get out there on the track as I have and do some of your own data gathering.

pimpin-tl

I rather trust NHTSA over what someone says on the Internet because that person thinks he is always right.

I hate cars

Awww. You came to back your girlfriend up. Cute. However, I can't find a single fact in your statement, just a personal attack.

pimpin-tl

Personal attack? I didn't mention names. I also just stated my opinion which there is nothing wrong in doing so.

I hate cars

We all know a government organization would never say anything misleading or wrong.

I don't think I'm right, I KNOW I'm right. If I doubted it, I would qualify my statements with such things as "I think" or "I'm not sure". You guys are offering no technical argument, you're just trying to win an argument by posting quotes the really don't even back you up.

You need to learn how to read between the lines.

I could show you how a turbo in some instances can help gas mileage. However, if someone asked me if a turbo increases or decreases mileage and I only had a short time to explain I would just say it hurts mileage. This is exactly what the NHTSA did in the quote. They are not wrong, they are making blanket statements to cover a very broad area.

Steven Bell

iTrader: (2)

OK guys, the pissing match is over. This has gone from informational to ridiculous.

Thread Closed.