There is about a 2 psi difference in the readings I get from the readout in the car and direct measurement on the tire. The car readout is usually 2 or 3 pounds lower than the one I get with a pressure gauge. I have two gauges, one mechanical and one digital, that tend to agree with each other. In order to get a 35 psi reading on the car readout I have to put in at least 37 psi in the tires. This is fairly consistent in all 4 tires. I feel the pressure gauge reading are probably the most accurate since I am getting the same reading from 2 different devices. Does anyone else have this happen? Is this fairly common?

 

I have the exact same issue. About 2 pounds different.

 

This is why Nissan got rid of the 'exact' reading displays on Zs after 06. too many threads like this...

 

±1 psi per the manufacturer

 

The question, if asked out of curiousity is understandable, but if asked out of obsession with 2 lbs of air, then relaxation is in order. In all due respect, Machines (including breathing, two legged ones) arent perfect and if your going to coexcist with them you have to show some leniency.

If I was a constant tire checker.. which Im not (I tend to walk the perimater and kick each one unless Im fixin to trip) Id put my faith (which I do) in a good digital. Prime importance is all round balance in PSI

 

Actually, a good analog dial gauge is much more accurate than the cheap digitals typically sold. Those pencil and cheap analog dial gauges are also notoriously inaccurate.

Getting the PSI "balanced" isn't that important or practical. If they're all low, that's a bad thing. And even though you set them all the same, once you sit in the car or fill it with gas, the corner weight shifts throwing all those pressure off anyway. Hell, a hour in the sun can raise the pressure on one side of the car 2psi higher than the other.

 

I was allowing for a "little" common sense---My bad. My point was 32 all around or 35 all around, not 17 all around.

And your right on the cheap gauges. Analog or Dig......Common sense. Whats priced cheap is cheap. And sometimes what isnt priced cheap is cheap

Its like alignment......If Im in a Gnats *** Mood, I'll sit in the car with a 3/4 tank of gas. If I'm not, I'll say ........I'll be back in an hour, snap to it.

 

My Configuration: I have a 2003 Performance model with TPMS.

The LCD cluster-gauge consistently displays very close (plus or minus 1 psi, so variance is maximum 2 psi) to the high-quality analog tire pressure instrument I use measuring tire pressure. I cannot tell you the brand. I purchased the device 20 years ago. It’s an analog instrument with a large easily readable face, and its label says “Perfect Circle.” I’m sure that you can purchase the same quality instrument today, but mine is very old (but still apparently very accurate).

As Dave mentions, using cheap (or even more expensive) devices won’t necessarily return accurate psi values. In fact, the “pencil” devices can be difficult to read, and a digital gauge I purchased a couple of years ago isn’t very inaccurate comparing this to the analog instrument I mention above.

I would also mention that low profile tires are prone to significant swings in psi. Moderate ambient temperature changes, varying road surfaces, driving speed, and even direct sunlight can noticeably alter your tires’ psi’s. If you measure your tires’ psi, and then begin driving, you might see a significant (2 or much more psi) variation.

--Spike