[ebhcr]

I did a search but didn't come up with much.

I'm running on the stock RS-A's, and yesterday morning I checked them for the first time since I took delivery back in Oct/Nov because I've been getting terrible fuel mileage. The door panel says it should be 32psi, but 3 of the tires were 24 and one was 26. Is this normal?

I went out and filled them up yesterday, came home today, checked them about 2 hours after I got home. All four of them dropped down to 28-29 range :x . Is there something wrong with my tires?

 

[zorminster]

nope, but there are thermodynamic laws in place. Compressing air creates heat- therefore it's specific volume increases. You pump it into the tire, it pressurizes. You go in, and that air cools down and the specific volume decreases- this decreases the pressure. Now- if you go out driving for a bit then check pressure again, you will be back up on your 30 or so PSI. check it out- if not, then there may be something wrong. Oh, and shoot yourself for not checking tire pressures in 5-6 months. Once a month at least man- its the only part of your car that actually holds you on the road; keep them in good condition.

 

[ebhcr]

Yeah, I'm sorry. I'm still learning. Only 16.

I'll take a little drive later and check again.

EDIT: Just got back. :? Every tire except for the passenger side rear tire is showing 28 or 29, the other having a little over 30 but not quite 31.

 

[Stulgs]

They should be 32 psi when cold. So, wait overnight or something, and then drive to the nearest gas station, unless you have a compressor at your house..

I had to fill mine up as well, and they were at 28psi Warm :shock:

oops.

 

[zorminster]

you 100% on that? I thought i remembered seeing my door-sill sticker saying it was 32 warm. which brings up a good point- check your yellow/white sticker in your driver side door sill and some where on there it tells you the pressure @ warm or the pressure @ cold- just make sure your speced to that. ebhcr- as long as your +- 2 psi you're fine. Honestly, I run mine a psi or two low because of how crappy these RSA's are- i can't get enough grip to feel safe if i run them at their recommended pressure. sure mpg suffers a little, but id much rather stay on the road.

 

[plazma]

Find a place that can fill them up with Nitrogen... its an inert gas.... wont act the way regular air does... doesnt get hot and expand... will last longer than air also... just a thought

 

[DrWebster]

The RSAs are supposed to be run at 35psi. I normally run mine at 37 (except when there's a lot of snow on the road, in which case I keep them at 35).

 

[eurotuner]

do make sure u dont have a nail or anything like that in there, happened to me and i thought it was just the weither.

 

[plazma]

[quote author=eurotuner link=topic=70852.msg1245050#msg1245050 date=1172874034]
do make sure u dont have a nail or anything like that in there, happened to me and i thought it was just the weither.
[/quote]

weather even LOL

 

[ebhcr]

It says "Cold tire pressure - 32psi" for both front and rear.

When I did check it in the morning the other day it hadn't moved all night. I'm still getting pretty bad fuel mileage, but that could be due to other things.

And I'm pretty sure it can't be a nail, because it's happening to all the tires, but one not so badly.

I'm going in for my first service next weekend so I'll get some insight, otherwise I can go to the local Discount Tire or something to see what they come up with.

 

[shenon]

for < $20. buy an air compressor. that way you don't have to drive somewhere to find an air pump -- heating up the tires all the way. Even the first mile or so can increase pressure noticeably. Especially if you throw in a few hard corners...that's what the Indy drivers do when following the pace car @ 80mph....drive all over the road to heat up the tires...knew it couldn't be loose steering linkage

And best not to let the dealer set your tire pressure....although you are in California, so it's probably not that cold outside. But in winter, I've had my dealer set the pressure to 32psi inside a warm maintenance bay!! Put the car back outside at -10 degrees and the damn pressure's down to 28psi....Now I tell them "don't even think about looking at my tires !!

 

[plazma]

i know people keep talking about filling it up with air and being careful about getting the tires too hot and heating up the air inside the tire...

like i said in a previous post... just put in Nitrogen if you have a place around you that does it... Nitrogen wont heat up like air and cause the problems you will have with air... you can add air to your tire if you have Nitrogen in them.. but you dont have to worry about condensation in the tires also... do some research on it.. its worth it to have it done

 

[ebhcr]

Is it something that's pretty common? I really don't know where to go for that.

I might be getting new tires anyways though, just because some of streets here aren't that great, and when it's raining I really don't feel any grip.

 

[wanta3]

I noticed when I still had all 4 RSAs that I could fill them to 32 and then a few weeks later find them all at 28; since i replaced the fronts with Bridgestones those haven't lost anything but the RSAs were both down the same amount.