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jacko15 05-04-2013 08:10 PM

Tire pressure monitor accuracy
 
Haven't seen any discussion on this, or maybe I missed it. I have a very accurate tire pressure gauge and it consistently reads 2 psi lower than the tire pressure monitor readings shown in the EVIC. Is there a way to calibrate the system, or do I need to take it to the dealer's service department?

bill_de 05-04-2013 08:16 PM

Re: Tire pressure monitor accuracy
 
I have one . RR, that reads 1 pound lower than my gauge. The other 3 are right on.

Since you know that you are off by 2 pounds, why worry about it.

BTW - when was the last time you checked your very accurate gauge. Is it just possible .... :)



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jacko15 05-04-2013 08:18 PM

Re: Tire pressure monitor accuracy
 
Good points Bill. Time to stop by Autozone!

Uncle Paul 05-04-2013 10:40 PM

Re: Tire pressure monitor accuracy
 
When you have one tire pressure gauge, you always know what your pressure is.

When you have two gauges...you are never quite sure : >)

The Evil Twin 05-05-2013 06:55 AM

Re: Tire pressure monitor accuracy
 
I have observed the same thing. I truthfully do have an accurate gauge that I verify once a month or so. I have the luxury of access to such equipment and race motorcycles so I am a bit OCD about pressure. I also calibrate my torque wrenches :)
Anyway, only 2 of my tires read accurately on the EVIC. The other 2 are off by 1-3 psig. I wish I had remembered to bring this up when I had the GC in for the FI problem. Oh well. Knowing the discrepancy is there, I just account for it. I actually think that having TPMS makes one more neurotic about pressure than normal. We used to just check our tires at each oil change!

doulos4JC 05-05-2013 05:32 PM

Re: Tire pressure monitor accuracy
 
Just had mine at the dealership. They verified the on-board system is reading correct pressures. Drivers front tire won't hold 42psi. Consistantly reads 35-37 soon after inflating to 42 psi. They supposedly found no problems with tire either. :confused:

jacko15 05-05-2013 08:38 PM

Re: Tire pressure monitor accuracy
 
Just curious, why 42 psi? The door plate says 33, doesn't it?

f1anatic 05-05-2013 09:27 PM

Re: Tire pressure monitor accuracy
 
Because you get better fuel economy / less wear with higher tire pressures. I have mine inflated to 42 as well. Admittedly, you also get less grip and at some point also longer braking distances. However, if I find myself on sand/trails/snow I will lower them. Until then they stay high.

doulos4JC 05-06-2013 05:29 AM

Re: Tire pressure monitor accuracy
 
Quote:

Originally Posted by jacko15 (Post 817639)
Just curious, why 42 psi? The door plate says 33, doesn't it?

Why 42 psi? It came from the factory with 42 psi. I ASSumed that was the optimal pressure. Door plate does say 33. The tire itself only says max. pressure 44 psi. Still have issue with front tire not holding preasure...ugh

bill_de 05-06-2013 05:35 AM

Re: Tire pressure monitor accuracy
 
Quote:

Originally Posted by doulos4JC (Post 817836)
Why 42 psi? It came from the factory with 42 psi. I ASSumed that was the optimal pressure. Door plate does say 33. The tire itself only says max. pressure 44 psi. Still have issue with front tire not holding preasure...ugh

The door plate should be your best pressure. My MDX came with too much air in the tires. When I questioned it they found that their prep guy always checks the tires and fills them to whatever it said on the tire. At least he was trying, just didn't know what he was doing.


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loveracing1988 05-06-2013 08:46 AM

I just filled my wife's yesterday to what my gauge read was 50 but it is 43 on the display, except for the left front which reads 2 psi higher no matter what.

peckmv 05-06-2013 12:32 PM

Re: Tire pressure monitor accuracy
 
I use a calibrated gauge and it too is off from the TPMS reading. Usually 1-3 lbs. Those that are running 42 psi you are using the center section of the tire and it will effect braking and handling. You will also wear out the tire much faster. Kinda negates the fuel savings. Really should be between 32 - 35.


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