NC Silver

I had a tire shop check my tire inflation and when I started the car, the left side (front and rear) tire pressures were 58 and 52 respectively. Then, a split second later they both went to 38 and 32. I've checked it and probably 3 times over a week I've noticed the glitch. You have to be quick to click the button to see the pressure. Just wondered if anyone else has experienced this.

rec

I noticed the 58psi in LF tire last week.

Inaccurate

Normal. Mine does it all the time. I am somewhat captivated/mesmerized by the TPMS display. I always check it while the engine is warming up. So, I am experienced in it's behavior.

Actually, the TPMS has three stages that it goes thru. And, you might or might not catch it in one of these stages.

Stage one is the "58" stage. This is the default value. It displays the 58 because it has "no clue" yet to the actual pressure.

Stage two is where it displays the previous pressure right before you turnd-off the car previously.

Then, of course, is stage three -- the real actual pressure. Sometimes (rarely), I catch the TPMS not really showing the actual pressure until I have rolled one city block. But, instead it is displaying the previous reading (what I called the Stage Two reading) until it gets a handle on the actually pressure. I have discovered this because I adjust my pressure at least once every two weeks. Or, in the mornings when it is much colder weather than when you parked the car the evening before. Did I mention that I am captivated/mesmerized by the TPMS. No, it is not a complusive disorder. No really, it isn't. No, no....

rec

Well, I've been paying a lot more attn to it lately as I guess I've got a little OCD and was trying to get the pressure set exactly as I wanted it in all 4 wheels and to figure out the calibration w/my manual gauge...an interesting exercise.

Inaccurate

From one OCD to another.. here is the trick to get them even.

Well, even from left to right. You will never get even pressure from front to rear because the fronts heat-up more than the rears.

Here is what I do.
1) Adjust only when cold (car not driven in over 12 hours). I ajust mine on weekends before driving it anywhere.
2) Add to your desired pressure PLUS a half psi more. My pressure gauge is digital with a readout to the nearest half psi (example: 32.0, 32.5, 33.0, 33.5).
3) So, if your desired pressure is 35.0 psi, then add air until your handheld gauge reads 35.5 (half psi more than the desired 35.0).
4) The reason we are adding more is so that we can SLOWLY bleed some air out of the tire until we hit 35.0.
5) Repeat the same procedure for the next tire where you SLOWLY bleed the air down to 35.0.

Consistent procedure will produce consistent (even) pressure in each tire.

rec

LOL...Thanks

I was pretty close. Doing first thing in mornings on weekend after car sat overnight. My handheld also is a digital in .5 increments. I thought I had it set right after checking the TPMS. Put the valve caps back on, got in the car to go and one tire according to the TPMS had changed by 1 lb. I just smiled and left.

coykiam

hey guys my TPMS went off last nite some pressure falling as low as 26psi on the Front left tire and 28 psi all around due to the suddent cold weather last friday nite here in ny. Just a quick question, at what limit will the TPMS beeps ? below 31 psi ?

I just put some air since my accugauge had the same pressure readings with the TPMS, and all were below due to the cold weather. Its around 35-37psi when they get warm. Is this the ideal for the stock 17 inchers ??

Will Y.

Go with the door sticker pressures or a couple lbs above when the tires are COLD; don't worry about what the tires read when warm.
Minimum 32F/32R; I run 36F/33R on my 5A ('05 6M recommended pressures are 35/32 while '06 5A is 33/32, I believe; higher front pressures reduce understeer).

Inaccurate

If the psi drops to 26 psi, the warning is tripped. It requires 29 psi to reset the warning (to make the warning disappear).