Tire Pressure and Cold Temp

bravery · 11-03-2006, 07:25 AM

Since it has starting getting colder here my tire pressure light is on when I first start my car in the morning. Then in about 15 minutes it goes off. Is it normal for the tire pressure to be low due to colder tempures or do I need to get my sensors checked?

**efusco** · 11-03-2006, 07:38 AM

Tire pressure will drop about 1psi for every 10 degree temp drop. It's certainly possible that one or all are lower than the threshold for the TPMS, then when the tires warm with driving the sensor goes off.

I'd check the cold temp pressures to see where you are. Good idea to juice them up to whatever pressure you're comfortable with to do what you can to minimize the cold weather MPG hit.

Rangerdavid · 11-03-2006, 07:42 AM

I check mine first thing in the morning when they're cold. I keep them at 42-40. When it first turned cold here, my light come on as well. Just check 'em at least once a week, best time, IMO, is in the morning before you have driven anywhere.

Good Friday to all......

sub3marathonman · 11-03-2006, 01:43 PM

I've just had that happen here in Florida with the first "cold" weather. I guess the tires were right on the border of turning on the light.

It did turn out that the pressure was about 28 psi, which is about 20% lower than the 35 psi called for in the front tires. So I guess the system is working as it should. Also, the light never went off, even driving for about 9 miles.

I did refill them to the 41 psi, 39 psi that people recommend.

john1701a · 11-03-2006, 03:05 PM

<div class='quotetop'>QUOTE(bravery @ Nov 3 2006, 06:25 AM) [snapback]343101[/snapback]</div>

Quote:

Is it normal for the tire pressure to be low due to colder temperatures...
[/b]

Your PSI has likely been well below the recommended minimum (35/33) for quite some time now... which acclerates tire wear, lowers MPG, and increases the likelihood of an accident.

The cold caused the threshold to be exceeded, hence the light coming on. It shuts off after the air inside warms up, but your tires are still in need of air right away.

This is one benefit of running higher PSI routinely. Forgetting to check often enough is a very common problem. More air available from the start helps.

galaxee · 11-03-2006, 03:23 PM

don't check your sensors before you check your tire pressure!

tires warm up as you drive, hence the light going off. sounds like you're right on the edge of the warning threshold. check your tire pressures, inflate accordingly, and reset your tpms. good time to check your spare tire pressure as well. seasonal changes bring about tire pressure changes.

Rangerdavid · 11-03-2006, 04:12 PM

<div class='quotetop'>QUOTE(galaxee @ Nov 3 2006, 03:23 PM) [snapback]343421[/snapback]</div>

Quote:

good time to check your spare tire pressure as well. seasonal changes bring about tire pressure changes.
[/b]

Excellent suggestion Galaxee!! I had not even thought about the spare!!

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11-03-2006, 07:25 AM	#1
bravery Join Date: Apr 2006 Location: Denver, CO Posts: 4 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	Since it has starting getting colder here my tire pressure light is on when I first start my car in the morning. Then in about 15 minutes it goes off. Is it normal for the tire pressure to be low due to colder tempures or do I need to get my sensors checked?

11-03-2006, 07:38 AM	#2
efusco Troll Slayer Join Date: Nov 2003 Location: Nixa, MO Posts: 18,040 My Car: 2004 Prius Model: Package: #9 Thanks: 102 Thanked 500 Times in 269 Posts Friends: 41	Tire pressure will drop about 1psi for every 10 degree temp drop. It's certainly possible that one or all are lower than the threshold for the TPMS, then when the tires warm with driving the sensor goes off. I'd check the cold temp pressures to see where you are. Good idea to juice them up to whatever pressure you're comfortable with to do what you can to minimize the cold weather MPG hit.

11-03-2006, 07:42 AM	#3
Rangerdavid Senior Member Join Date: Jun 2006 Location: Boone, North Carolina Posts: 1,279 My Car: 2006 Prius Model: Package: #5 Thanks: 1 Thanked 15 Times in 7 Posts Friends: 25	I check mine first thing in the morning when they're cold. I keep them at 42-40. When it first turned cold here, my light come on as well. Just check 'em at least once a week, best time, IMO, is in the morning before you have driven anywhere. Good Friday to all......

11-03-2006, 01:43 PM	#4
sub3marathonman Senior Member Join Date: Aug 2005 Posts: 247 My Car: Model: Package: Thanks: 0 Thanked 17 Times in 14 Posts Friends: 0	I've just had that happen here in Florida with the first "cold" weather. I guess the tires were right on the border of turning on the light. It did turn out that the pressure was about 28 psi, which is about 20% lower than the 35 psi called for in the front tires. So I guess the system is working as it should. Also, the light never went off, even driving for about 9 miles. I did refill them to the 41 psi, 39 psi that people recommend.

11-03-2006, 03:23 PM	#6
galaxee resident lab rat Join Date: Mar 2005 Location: south of lake Michigan Posts: 9,736 My Car: 2005 Prius Model: N/A Package: #5 Thanks: 0 Thanked 130 Times in 53 Posts Friends: 26	don't check your sensors before you check your tire pressure! tires warm up as you drive, hence the light going off. sounds like you're right on the edge of the warning threshold. check your tire pressures, inflate accordingly, and reset your tpms. good time to check your spare tire pressure as well. seasonal changes bring about tire pressure changes.