Dash Tire Pressure gauge reading Per Tire

How accurate is the tire pressure gauge reading per tire on the dash ? I check the air when cold with a good hand gauge, Never reads the same on the dash, Usually higher by a couple of pounds

Thanks Tom C.

 

I think you just answered your own question

 

Get a new hand gauge..!!

 

Mine is accurate compared to my Blue Point dial and Topeak digital gauges.

 

I would say pretty accurate from my experience

 

they are extremely accurate as they are safety equipment
[but there can be specific reasons they become inaccurate]

use a racing gauge like motion pro (100 bucks) if you want to compare pressures, or at very least something digital like accutire

 

I like the Pressure Gauge style that clips onto the valve stem as I'm adding/deleting air...... Seems to be dead-on....!!

Looks like this....

 

I agree with what folks have posted. Mine is right on with my gauge.

 

Mine is pretty on the money. My tires were super low before bring them into service, they filled them up and it now reads what it should. When its cold it drops by 3-4 and when its warm its up by 2-3.

 

Yes That is what I am seeing also, so I guess that is my answer

Thanks Tom C.

 

I have just put on my winter rims with non factory tis and info won t show anything . Any clues why

 

My truck gauge reads lower than my hand gauge.

 

Kind of related...
Doesn't tpms measure absolute pressure and gauges measure differential pressure?
If so, does the ECU use atmospheric pressure to recalculate?

 

Mine (hand gauge and TPMS display) are within 1 psi of each other.

 

kinda. The sensors do in fact read absolute and a gauge reads “Gauge pressure”. But the sensors would actually read something like 14psi lower at sea level and 10psi lower at 10k feet than people would expect. So the sensors are calibrated to absolute being ~14.4 psi rather than 0. And there is no ECU Re-calibration / calculation. What the TPS sends is what the TPMS displays. So at sea level you’ll be spot on and at 10k feet your Dash will be ~4psi out to your typical gauge.