TPMS questions.

[davidm]

A couple of days ago the tire pressure warning alarm came on on my 2010 Insight. This coincided with a drop in temperature so I guessed the temperature drop caused the pressure to drop in the tires.

According to the owners manual and the chart on the door panel, the pressure, front and rear, should be 33 PSI. I checked it with a cheap mechanical gauge (one of those things with the rod that pops out and has PSI gradations etched on it) and it showed each tire as having 32 PSI. Keep in mind that this gauge only has marks for every 2 PSI. It can of course show a reading between the 32 and 34 marks, but I'm not sure that it's even accurate down to 1 PSI.

It was warmer today and the alarm is no longer showing. I suppose if I had added 1 PSI to each tire it would have come back on today to indicate I was over pressure.

Is the TPMS really sensitive down to 1 PSI? If so am I going to be experiencing this a lot? Should I be constantly chasing small temperature induced changes in pressure?

Keeping the PSI that precise will be a pain. One thing I can do is get a better pressure gauge. But another issue is the fact that gas station air hoses no longer have a way to select a pressure. You just add some air, check the pressure, add some more, etc. hoping that your quarters hold up.

Anyone else experience this kind of on then off TPMS alarm behavior? Is it really sensitive down to 1 PSI? Is there something else going on, a problem with a senor maybe?

[vegajf51]

It won't come on if your tires are over-inflated just under. I have 38 psi in all my tires.


Sent from my Autoguide iPhone app

[davidm]

Why 38? I'm assuming that 33 is optimum, since that's the recommendation. Is 38 better for some reason?

[jcbesq]

more pressure = higher mpg's ... most tires (especially the newer lrr's) can take the extra pressure, but if abnormal treadwear/handling squigyness develops then go back to stock ... i'm keeping mine at 38 allaround and wear has been even and ride about the same

[davidm]

If you inflate to 38, is there a way to reset the TPMS to alert you if it goes below that?

[jcbesq]

while the mid has alot of fuunctions, I don't think that's one of them

[Jayemtee]

38 shouldn't hurt. Many people here run 48 which is at the limits of my comfort zone.

Tire temp and ambient temp are factors too. Perhaps you should over inflate them in the afternoon, then adjust to your target temp before you start out in the cool morning.

[davidm]

So, if 38 is better, why is 33 the recommended pressure?

[wowwee]

Everything about a car is a balance of various things, in this case, ride quality, efficiency and safety.

[davidm]

So inflating beyond 33 would compromise safety?