Hello all I just bought my G a month ago and I live in Chicago. When the outside temperature drops below about 20 degrees my low tire pressure light comes on. I have checked the tire pressure, which really sucks when its -2 outside, but anyways they are fine. When the temp gets warm the light turns off. Any suggestions?

 

what PSI are they at and what year rim/tire size G coupe?

 

Pressure should be at 32 psi before you start driving it. Look at the door jam for the exact specifications.

 

There are a lot of threads about this - I think the pressure drops something like 1psi for every 10 degrees F drop in temperature. So even if you tires were at spec (i.e. 32 psi) at 50 degrees, by -2 they'd only be 27 psi or so, and might set off your TPMS (Tire Pressure Monitoring System).

I know you said you checked the pressure outside at -2 and they were to spec, but it probably can't hurt to add a little bit more air so that the warning goes away. This same thing happened to me the first really cold day we had - I added air and within a few minutes of driving the light went off and hasn't gone on since.

 

i added a little air and the light went off after driving a little...it did warm up a bit today so well see what happens when the temp drops again....thanks for the help

 

Spec is 32? I could've sworn the door sticker says 34...

Also... Are you filling your air at the gas station, or do you have your own compressor? I've never seen a gas-station run an in-line dryer (to remove moisture from the air). Every gas-station compressor I've used sprays a mist of water with the air... If you have any moisture in the air, it will expand/contract MUCH more with temperature than dry air. I have my own compressor... When I installed a $20 line-dryer to my compressor, my problems went away... (Plus if you have air-tools, they will thank you for installing a line-dryer)

 

yeah ive been filling at the gas station but i have a friend with a compressor so i guess ill fill at his house now thanks

 

That's way I said look at the door jam for the exact specifications.

I don't expect gas stations to maintain their compressors unless it's broken. Which means there's probably a puddle of water forming at the bottom of the tank.

 

Yeh its normal for the tire pressure sensor to go off when its cold. I know some people do Nitrogen fills and stuff.

 

What he ^^ said. The dealer said lots of people call about it and it goes back to normal when the temp does.

 

i guess im a little relieved that im not the only one with this problem....im moving somewhere warm soon....CALI here I come!!!!!

The G is comin with me too

 

High School Physics- Chemistry teaches Boyles Law:
http://en.wikipedia.org/wiki/Boyle's_law.
"i guess im a little relieved that im not the only one with this problem"

What problem the way world works.

 

I wasn't slammin' you, I was just saynig that if it was 32, than I'm over-inflating my tires

But I just checked the door... It should be 35, so I've still been underinflating them.

 

Remember the inflation sticker PSI is a COLD PSI before the car is driven at the coldest ambient of the day,

The electronic system is an end of the line EMERGENCY WARNING, it doesn't relieve you of obligation to manually measure and adjust tires weekly as the ambients change.

You can never over inflate a tire as long as the worst case peak doesn't exceed the sidewall limit [44-50-51 varies by brand] after hours of driving at extreme warm ambient.

Tires are tested at max psi for hours at 100% rated load.

 

Hot air makes things expand...and cold air shrinks things...works for everything even the human body lolol