Can you rely on the EVIC readings of each tire or should I do the old fashioned method of using a tire gauge?

You'll probably find there is a consistent difference between the evic and a tire gauge. I have several gauges from digital, to the old stick style and even those vary by a pound or two between them. I'd take several readings and compare over the course of a few days (cold and hot) and just see what the differences are. I try to always take my readings at night after the car has sat for a good couple of hours that way there's no variance from the sun heating up the tires on one side of the vehicle.

I filled up my tires using a very accurate gauge. After doing so the EVIC although a good guide to a major problem is not very accurate.

As mentioned by todde702 taking the pressure reading when the tire is cool and on level ground is key. Best to use a separate gauge, but still use the TPMS as a guide to spot any serious problems.

I ought to let the air out of a tire just to see if the TPMS works!!!

I ought to let the air out of a tire just to see if the TPMS works!!!

Please note:

The sensors lay dormant (Park Mode), then wake and start transmitting (Drive Mode) when the vehicle first reaches speeds over 15 mph (24 km/h). Once the wheels stop rotating for a period of approximately 20 minutes, the sensors shut down until again awaken. Although not transmitting as when in Drive Mode, while in Park Mode, the sensors still transmit approximately once every 13 hours to let the receiver know air pressure status at that time. Sensors will also transmit when a pressure change of one psi (seven kPa) or more is detected during that period. For more information on sensors, (Refer to 22 - TIRES/WHEELS/TIRE PRESSURE MONITORING/SENSOR - OPERATION).

Please note:

The sensors lay dormant (Park Mode), then wake and start transmitting (Drive Mode) when the vehicle first reaches speeds over 15 mph (24 km/h). Once the wheels stop rotating for a period of approximately 20 minutes, the sensors shut down until again awaken. Although not transmitting as when in Drive Mode, while in Park Mode, the sensors still transmit approximately once every 13 hours to let the receiver know air pressure status at that time. Sensors will also transmit when a pressure change of one psi (seven kPa) or more is detected during that period. For more information on sensors, (Refer to 22 - TIRES/WHEELS/TIRE PRESSURE MONITORING/SENSOR - OPERATION).

Interesting....Mine doesn't work that way at all...When I add/remove air out of the tire with the engine shut off, but the ignition on so that I can see the EVIC display, it updates every minute or so. I didn't have to take it down the road for it to update,

Maybe it's a change in the computer from the 07' models???

Or the increase (or change) of pressure wakes them. Driving down the road will start heating the tires causing the pressure to rise.

I ought to let the air out of a tire just to see if the TPMS works!!!

It works! I drove thru a construction zone a week or so ago, picked up a nail and had a slow leak. It showed 24 psi on the RR when all the rest were 32. I then pumped it up to 32, and when I came back hours later, it was 14. Time to put on the spare!

Accuracy isn't really the issue, I think, just showing trends and monitoring is the best feature/value of the tpm.

My tire guy told me to always use the valve that came from the tire, not just another generic. Says they're stainless.

Yes, I agree with Jack. They do work quite well, but not as an exact measurement. Use a gauge for that.

If you have a nail or other problem with your tire it will catch it much earlier.


It works! I drove thru a construction zone a week or so ago, picked up a nail and had a slow leak. It showed 24 psi on the RR when all the rest were 32. I then pumped it up to 32, and when I came back hours later, it was 14. Time to put on the spare!

Accuracy isn't really the issue, I think, just showing trends and monitoring is the best feature/value of the tpm.

My tire guy told me to always use the valve that came from the tire, not just another generic. Says they're stainless.