Which to trust, TPMS or Gauge?

Professor///M · 08-18-2017, 08:09 AM

Don't know if this has previously been asked, but which one is more accurate?

Do I trust my tpms sensor of the actual tire pressure or my BMW digital gauge?

My TPMS reads 1psi lower than the digital gauge.

Just curious.

Thanks!

gatorfast · 08-18-2017, 08:02 PM

Definitely the gauge is more accurate. My tpms consistently reads lower than my gauge as well.

Professor///M · 08-18-2017, 10:24 PM

Quote:

Originally Posted by gatorfast

Definitely the gauge is more accurate. My tpms consistently reads lower than my gauge as well.

That's what I thought since I notice variability between my 2 vehicles.

Thanks!

TurboM · 08-19-2017, 01:10 AM

1 psi variance? seriously?

dzvero · 08-19-2017, 01:47 AM

OP you beat me to this. Couple days ago i saw one of my tires is 31,2 psi cold and went to inflate . The inflation was automatic and setup to 35. at that time the reading was 32 something but wont inflate .

Professor///M · 08-19-2017, 05:50 AM

Quote:

Originally Posted by TurboM

1 psi variance? seriously?

Sometimes 2-3. Depends. That's why I'm here asking a question.

F32Fleet · 08-20-2017, 09:38 AM

Depends on the accuracy of your gauge. 1/2 psi is about the best you're going to get on a high end temperature compensated automotive analog gauge (dial 3" or less in diameter). Digital gauges are of course much more accurate but the ones which can compensate for temperature are much more accurate.

Ian1973 · 08-24-2017, 07:43 PM

Quote:

Originally Posted by TurboM

1 psi variance? seriously?

I know right, I'm surprised the Earth didn't stop rotating.

katit · 08-25-2017, 03:11 PM

I have digital gauges. Yes, TPMS is about 1-2 psi off

Draper · 08-30-2017, 10:20 PM

Quote:

Originally Posted by F32Fleet

Depends on the accuracy of your gauge. 1/2 psi is about the best you're going to get on a high end temperature compensated automotive analog gauge (dial 3" or less in diameter). Digital gauges are of course much more accurate but the ones which can compensate for temperature are much more accurate.

Any models in particular you'd recommend?

F32Fleet · 08-31-2017, 05:56 AM

Quote:

Originally Posted by Draper

Quote:

Originally Posted by F32Fleet

Depends on the accuracy of your gauge. 1/2 psi is about the best you're going to get on a high end temperature compensated automotive analog gauge (dial 3" or less in diameter). Digital gauges are of course much more accurate but the ones which can compensate for temperature are much more accurate.

Any models in particular you'd recommend?

I have one of their low end digital gauges.

http://www.longacreracing.com

dmk08 · 08-31-2017, 08:35 AM

I had this issue recently. My manual guage was reading 32-33 PSI but my car thought they were 29 PSI. Actually caused my TPMS to go off. After a reset of the system (and adding no air) it has the correct values.

tom @ eas · 08-31-2017, 11:22 AM

TPMS to monitor, pressure gauge to validate.

08-18-2017, 08:09 AM	#1
Professor///M Brigadier General 819 Rep 3,341 Posts Drives: 2022 M3, 2022 X5 40i; Join Date: May 2007 Location: Northeast iTrader: (5) Garage List 2022 BMW M3 Comp. [0.00] 2016 BMW X5 35i [10.00]	Which to trust, TPMS or Gauge? Don't know if this has previously been asked, but which one is more accurate? Do I trust my tpms sensor of the actual tire pressure or my BMW digital gauge? My TPMS reads 1psi lower than the digital gauge. Just curious. Thanks!
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08-18-2017, 08:02 PM	#2
gatorfast Major General 4995 Rep 6,862 Posts Drives: 718 Cayman Join Date: Jan 2008 Location: SoFla iTrader: (4)	Definitely the gauge is more accurate. My tpms consistently reads lower than my gauge as well.
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08-19-2017, 01:10 AM	#4
TurboM Captain 252 Rep 674 Posts Drives: 2018 F82 M4 ZCP Join Date: Nov 2013 Location: Atlanta iTrader: (1)	1 psi variance? seriously?
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08-19-2017, 01:47 AM	#5
dzvero Lieutenant Colonel 529 Rep 1,514 Posts Drives: 2015 M$4 F82 Join Date: Dec 2015 Location: CA iTrader: (2)	OP you beat me to this. Couple days ago i saw one of my tires is 31,2 psi cold and went to inflate . The inflation was automatic and setup to 35. at that time the reading was 32 something but wont inflate .
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08-20-2017, 09:38 AM	#7
F32Fleet Lieutenant General 3570 Rep 10,351 Posts Drives: 2015 435i Join Date: May 2005 Location: Southeastern US iTrader: (0)	Depends on the accuracy of your gauge. 1/2 psi is about the best you're going to get on a high end temperature compensated automotive analog gauge (dial 3" or less in diameter). Digital gauges are of course much more accurate but the ones which can compensate for temperature are much more accurate. __________________ "Drive more, worry less. " 435i, MPPK, MPE, M-Sport Line
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08-25-2017, 03:11 PM	#9
katit First Lieutenant 89 Rep 302 Posts Drives: 2017 F80 Join Date: Jun 2016 Location: STL iTrader: (0)	I have digital gauges. Yes, TPMS is about 1-2 psi off
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08-31-2017, 08:35 AM	#12
dmk08 Gone Fishin’ 7318 Rep 12,125 Posts Drives: Walks Join Date: Jul 2012 Location: Atlanta iTrader: (19)	I had this issue recently. My manual guage was reading 32-33 PSI but my car thought they were 29 PSI. Actually caused my TPMS to go off. After a reset of the system (and adding no air) it has the correct values.
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08-31-2017, 11:22 AM	#13
tom @ eas BimmerPost Supporting Vendor 8115 Rep 18,814 Posts Drives: BMW Join Date: Nov 2005 Location: Anaheim, CA iTrader: (19) Garage List 2018 BMW i3s [0.00] 2010 BMW M3 [6.50] 2015 BMW M4 [5.25]	TPMS to monitor, pressure gauge to validate. __________________ Tom G. \| european auto source (eas) email: tom@europeanautosource.com · web: https://europeanautosource.com· tel 866.669.0705 · ca: 714.369.8524 x22 GET DAILY UPDATES ON OUR BLOG · FACEBOOK · YOUTUBE · FLICKR · INSTAGRAM
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