Every 4-3 weeks i get a TPMS light. So i fill my tires up using the compressor that came with the car, no problem with me.

My question is, over a 3-4 week period, is it normal for a car to lose some tire pressure? Is this just happening to me, or is anyone else experiencing this?

that is not normal. after the first week of ownership, my tpms light was lit, turned out that i had picked up a nail. that was the only time tpms came on and stayed on. (came on after leaving car at 9000+ elevation for 5 days, after driving about 10 minutes, the light went off). i would get it checked out at the dealership. it is not normal.

within 3-4 weeks its not unusual to lose some air, but losing enough air to turn on the sensor light seems a little excessive. Does this happen with all of the tires or just one of them.

In 6 months, I haven't lost more than a pound of pressure.

Fitting metal valve caps with an integral seal in them will stop any air escaping past the valve......this is a common cause of tyre pressure drop. It's a cheap fix too.....there's even a DIY thread on it :D

Gomez.

i have 2.2 bars on all tires'

1 bar is about 15 psi correct?

using that math im at 34-35 PSI. when does the TPMS go on?

its all tires.

i have 2.2 bars on all tires'

1 bar is about 15 psi correct?

using that math im at 34-35 PSI. when does the TPMS go on?

its all tires.


The TPMS System (http://www.finishlineperformance.com/rx8/docs/02-002-03.html) will turn the light on if the pressure is below 26 PSI or above 49 PSI.

What you're experiencing is not normal. I typically lose 0 to 0.5 PSI in two weeks with my stock wheels/tires/caps.

What the heck are you using to measure your tire pressure in bars LOL :) ? Bars are for drinking beer :D.

Make sure you use a good quality tire pressure guage to set each tire to 32 PSI COLD if you've not been doing that already.

rx8cited

[QUOTE=rx8citedWhat the heck are you using to measure your tire pressure in bars LOL :) ? Bars are for drinking beer :D.
rx8cited[/QUOTE]

The air compressor that comes with the 8 measures in bars IIRC.

that is alot of preassure to lose. Mine comes on if the preassure drops below 28 pounds, or if it's below 5 degrees outside. I normaly try to keep them at 33psi. It sounds like you have one or multiple bad valves. Any dealer should be able to change all of them for free. It's about a 5 cent part.

... 1 bar is about 15 psi correct? ...


1 bar = 2 mixed drinks :D

Close, actually 1 bar = 14.5 PSI
so 2.2 bar = 31.9 PSI ~ stock tire pressure spec 32 PSI cold.

You should be fine with 2.2 bar, assuming the pump guage is accurate.

rx8cited

My pump gage is not accurate. I have to put in 2.5 bar to get my tires to 33 psi which is where I like to run them. If the gage was accurate I would only have to put in 2.27 bar. :eek:

So someone please answer me on what is the correct PSI for the stock 8??? I've searched this forum and have seen everything from 28-40 PSI. Sorry if this is a stupid question but I'm not really a tech head but just love my car.

You can read it on your tire. It should say 2200 bar and 32 psi.

You can read it on your tire. It should say 2200 bar and 32 psi.

No, the tire is not the correct place to find the normal operating tire pressure.

Look at the Tire Pressure Label inside the driver's side door jam or page 8-23 of your Owner's Manual. 32 PSI cold is what it says. Make sure you check the pressure when the tires are cold.

Since we're on the subject, snow tires get 34 PSI cold per our manual.

rx8cited