Low Tire Pressure Question...

[PlatinumRespect]

In my sonata, the Low Tire Pressure warning came on and was pretty much locked into my dash for about 3-4 days. I kept telling myself I would get around to putting air in, but never got around to it...

Eventually, the light turned off and the warning went away completely. Does this mean I still have low tire pressure, and it just shuts off the warning after a period of time? Or was it something else giving it a false reading?

[ssmuff]

Temperature change most likely caused the light to come on. You had low pressure but the tires warmed up enough to show a higher psi. I would still go have them checked/filled. Again why are you going days when a light is on????? Those lights on that dash means something is WRONG!!!!!!!!!!!

[Smutty]

To elaborate; the fault could be the tire pressures are too low, too high, broken sensor, dead battery in your sensor, computer losing the ID of a sensor or an actual computer fault regarding your TPMS.

Double check your cold pressures and make sure they're right. If the pressures are borderline then you could see it come into spec with temperature changes and increases while driving.

Nitrogen is less susceptible to changes in temperature but make sure that you're actually getting nitrogen and not just being told you're getting it.

[rkcann]

Definitly sounds like a pressure loss and gain due to temperature change.

ssmuff is correct that you should not be going days without investigating the cause of a dash light...you could have been setting yourself up for a tire failure while driving 65 on the highway.

[Smutty]

tire blowout at 85 mph caught on dashcam - YouTube

[jglopic]

I've had a couple tires go while driving. Never lost control like that dash-cam video. I would wager that two things happened in that video. 1) The car pulled to the right, causing the driver to sharply coutersteer to the left. 2) The driver hit the brakes when the tire blew out.

Both of these driver reactions are completely normal. They are also completely wrong. If you ever have a tire go down while driving, maintain approximately the same throttle position and use only small steering wheel inputs to keep from hitting anything else. Once the car control is maintained, then you can gradually slow down and stop safely.

Think about it this way: on the cops videos where they use spikes to take out a suspect's tires, how often do you see the vehicle spin immediately? It is rare. That is because the suspect never takes his or her foot off the gas pedal and continues to keep the car pointed straight.

See this article from Motor Trend in 2004, which they wrote with the assistance of Michelin Tire's proving grounds team.

[big_ol_meat]

Originally Posted by Smutty

Nitrogen is less susceptible to changes in temperature but make sure that you're actually getting nitrogen and not just being told you're getting it.

I've never had a problem until they put the "nitrogen" in. I get the low tire warnings every time a place puts nitrogen in it. Happens within a few weeks. Same with my friends. I recommend good ole compressed air.

[ryster]

A tire loses 1psi for every 10 degree drop in temperature. Even if the temperature outside goes from 70 degrees to 30 degrees, you are only going to lose 4psi in the tires. If the tires were low to begin with, then the light may come on. However, if the tires are properly inflated a temperature drop should not cause the light to come on (for example, going from 34psi to 30psi.) I live in an area of the country where we get into the single digits in the winter, and I have never had a false TPMS reading on a cold morning.

I keep my tires at 35psi, and regularly check them. I consider the TPMS an emergency indicator as opposed to a maintenance reminder.

[Danno]

Originally Posted by ssmuff

Temperature change most likely caused the light to come on. You had low pressure but the tires warmed up enough to show a higher psi. I would still go have them checked/filled. Again why are you going days when a light is on????? Those lights on that dash means something is WRONG!!!!!!!!!!!

The OP is from Jersey. He may have other things to worry about....

[K1LLROY]

DUDE! Just check your tire pressure...geez