I once compared my tire pressure with TPMS and those tire pressure pen gauge, and find that they are 5PSI differences!!

You know how your tires are always over pumped from the dealership, and you go home and let the air out yourself.

So I go home and measured it, the air pressure I got from the pen gauge is 35PSI, while the TPMS pressure shows 30PSI. Anyone has those type of experience?

Which one is more trustworthly? I'd like to keep the tire pressure to be in the range of 32PSI or so. Thanks!!

 

Mines were almost exact. Do you have a good gauge? Because if you have one of those cheap ones that look like a pen, they suck. Long time ago I spent like $25 buks for a gauge, and it still works great and extremely acurate. its also made well and durable.

 

+1, my tpms is usually within 1 (2 max) of the gauge.

 

My TPMS is off a couple PSI. I set all my tires at about 33 psi and 2/4 show 33 psi and the other two are off 1-2 in either direction consistently.

 

I am a fanatic over keeping precise tire pressures. And being in Connecticut with the temps now falling I have to keep an eye on it. As the daily ambient temperature falls, so does the PSI. I have, what I think is a decent handheld gauge that I have used for years, and set the tires by it. The TPMS always seems to read about 1 to 2 PSI lower than my gauge. I just go by my gauge but do use the TPMS readout to make sure all four corners are at least the same number PSI. I also like to set my tires just a tad higher than the recommended 32 PSI cold. I set them for a cold reading of 34 PSI. TPMS displays 33 at all four corners.

 

Here is the explanation from Acura about the difference from the May 2006 TSB: http://www.in.honda.com/Rjanisis/pubs/SN/B060500.PDF

 

I use an electronic gauge. It's always been dead-on with the TPMS readings.

 

some gas stations have a digital air pump....set the psi and it does the rest. 2 qtrs can go a long way in terms of getting all 4 tires @the same pressure regardless of the car reading.

did it last nite and the reading @ the station and tpms were the same.

 

Thanks for the link. Interesting, although I don't think the difference of 1-2 PSI I get between my gauge and TPMS is due to altitude since I'm pretty much at sea level. I'm maybe 70 ft above sea level at most which would make the difference virtually immeasurable.

Maybe I need a new gauge!

 

I don't think you need a new gauge. You have to take temperature into account too. For every 10 degrees up or down the pressure in the tires will change 1 psi +/-. So, it's important to check the pressures often, especially in the winter. It's always better, and safer, to overinflate your tires, but not higher than 36 psi in the winter if you car is in a heated garage. Underinflated tires (24 psi or less) are dangerous winter or summer.

 

Correction: Never inflate your tires higher than 39 psi.