so..yes i know how much psi im suppose to run on my tires and yes i had my tpms sensors properly mounted professionally. and i understand tire psi goes up in higher temp and lower in lower temp.
but my question is.. my psi gauges in my car reads 32-36 most of the time, which i assume might be normal. but just today i decided to check with a actual air hose at my uncles shop. when i stick it in, it reads 40-41 all around. after i get back in my car and drive 20mph to see what my gauges say, its still around 32-36, so i drive back into my uncles shop and tried 3 different air hose, they all read 40-41.
so, what am i suppose to go by? what the air hose tells me or what the gauges in my car tell me?

 

Obviously, one of the two instruments you are using to measure psi is not accurate.

I've found that the gauge in an air hose isn't the best way to measure your tire's psi. I have a good analog gauge with a round face that measures psi very accurately. The psi reading on my 2003 Performance model's digital instrument cluster seems to be very accurate (always measuring close to my handheld analog instrument).

Your solution is using a third instrument to measure the psi. The two that are in agreement are probably giving the accurate reading.

--Spike

 

Get something like one of these Quickcar pressure gauges...



I used to have three or four cheap gauges lying around and they all measured different pressures and none of them were right. The Quickcar gauge and my TPMS sensors are almost exactly right on all the time.

 

^^thanks ill try that out tmr. and the 3 airhoses i used were all different. 1 of them looks like that quickcar pressure guage. i get what you guys are saying tho i know some friends that have pressure gauges also ill give them a try

 

Check this gage. Very accurate and easy to use: http://images.google.com/imgres?imgu...%3Den%26sa%3DG