Ambient Air Temperature

EZT · 08-25-2025, 07:34 PM

Gentlemen,

My 2009 Z’s air temperature for outside has been going up to 120+F. Now, it is indeed hot in Florida, but even when I get in it during a hot day it starts at 100 and cranks up to 120+. I assume that gauge itself is old and causing the issue. Has anyone replaced this or experienced the issue before? Minor problem but figured I could correct it.

Spooler · 08-25-2025, 09:27 PM

It can get that hot down here if the car is out in the sun. Does the temp drop once you get up to speed? 55mph or so?

EZT · 08-26-2025, 07:07 AM

I’ve had it down here for 14 years and I’ve never seen it go above maybe 112.

And to answer that question it continues to climb even when I get up to speed. I can’t quite figure out its break even point where it then decides to recede back down to “normal” air temperatures. Last time, it probably took 30 minutes driving on the interstate before it retreated back to 100.

cooltoy · 08-26-2025, 10:14 PM

AI - "Cars measure air temperature using a thermistor, a sensor that changes its electrical resistance with temperature. It's location could be behind the grille, or under a fender.These readings can be inaccurate on hot days because the sensor picks up heat from the road surface, not just the air. On hot, sunny days, the sensor's proximity to the road means it absorbs heat radiated by the asphalt, as well as air temperature. This results in a temperature reading that can be significantly higher than the true air temperature, as it's influenced by both the air and the road's heat."

In the 370Z the sensor is located low in front of the radiator, to keep it away from the heat of the engine. It is a replaceable item.

EZT · 08-27-2025, 09:29 AM

Cooltoy really appreciate that post with part #.

It’s of course fluctuated over the years here in Florida, but never have I seen it go so high until recently. Considering the cars age though I’m not surprised if the sensor has lost its touch.

cooltoy · 08-27-2025, 02:50 PM

Glad to help.

08-25-2025, 07:34 PM	#1 (permalink)
EZT Track Member Join Date: Mar 2011 Location: Gainesville Posts: 550 Drives: 09 370z Rep Power: 316	Ambient Air Temperature Gentlemen, My 2009 Z’s air temperature for outside has been going up to 120+F. Now, it is indeed hot in Florida, but even when I get in it during a hot day it starts at 100 and cranks up to 120+. I assume that gauge itself is old and causing the issue. Has anyone replaced this or experienced the issue before? Minor problem but figured I could correct it.

08-26-2025, 10:14 PM	#4 (permalink)
cooltoy Elite Member Join Date: Jun 2012 Location: Calgary Posts: 14,006 Drives: 14 PW 370Z S/T MT Rep Power: 243724	AI - "Cars measure air temperature using a thermistor, a sensor that changes its electrical resistance with temperature. It's location could be behind the grille, or under a fender.These readings can be inaccurate on hot days because the sensor picks up heat from the road surface, not just the air. On hot, sunny days, the sensor's proximity to the road means it absorbs heat radiated by the asphalt, as well as air temperature. This results in a temperature reading that can be significantly higher than the true air temperature, as it's influenced by both the air and the road's heat." In the 370Z the sensor is located low in front of the radiator, to keep it away from the heat of the engine. It is a replaceable item. EZT, Memphis370Z and sx moneypit like this. __________________ Member of kenchan's "photoshopped mods" and "proper offsets" gang. Last edited by cooltoy; 08-26-2025 at 10:22 PM.

08-27-2025, 02:50 PM	#6 (permalink)
cooltoy Elite Member Join Date: Jun 2012 Location: Calgary Posts: 14,006 Drives: 14 PW 370Z S/T MT Rep Power: 243724	Glad to help. __________________ Member of kenchan's "photoshopped mods" and "proper offsets" gang.

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08-25-2025, 09:27 PM	#2 (permalink)
Spooler A True Z Fanatic Join Date: Jun 2014 Location: Ga Posts: 14,149 Drives: 2013 Nismo 370z Rep Power: 2684394	It can get that hot down here if the car is out in the sun. Does the temp drop once you get up to speed? 55mph or so?

08-26-2025, 07:07 AM	#3 (permalink)
EZT Track Member Join Date: Mar 2011 Location: Gainesville Posts: 550 Drives: 09 370z Rep Power: 316	I’ve had it down here for 14 years and I’ve never seen it go above maybe 112. And to answer that question it continues to climb even when I get up to speed. I can’t quite figure out its break even point where it then decides to recede back down to “normal” air temperatures. Last time, it probably took 30 minutes driving on the interstate before it retreated back to 100.

08-27-2025, 09:29 AM	#5 (permalink)
EZT Track Member Join Date: Mar 2011 Location: Gainesville Posts: 550 Drives: 09 370z Rep Power: 316	Cooltoy really appreciate that post with part #. It’s of course fluctuated over the years here in Florida, but never have I seen it go so high until recently. Considering the cars age though I’m not surprised if the sensor has lost its touch.