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High Ambient Temp- Cause for Concern?

SrsBsns

Active member
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Location
San Diego
#1
Hey Guys,

I took my '15 down to Ensenada over the weekend. It was a great trip with some amazing roads. But on the way home, I got stuck at the border crossing.

We went onto the border website and wait times were listed at 2 hours. It took over 6 times that estimation. I spent 13 hours at the border, just waiting.

I got there around 8 and it was about 60-ish degrees out. Traffic was inching up normally until about 10 when it pretty much just stopped for the night. We'd move up one car length every 15-60 minutes for the whole night. I would let the FiST idle for a while, but if we weren't moving for too long, I'd turn it off. Overnight it was fine.

In the morning, when the sun came out, it started getting a little warmer outside. Probably got up into the 70's. But my ambient temps were reading 98, 99, 100... I think the hottest it read was 102. And it was nowhere near that outside.

I didn't bring my AP with me on the trip, so I couldn't monitor my coolant temps outside of the idiot gauge which stayed dead center the whole time. But I was worried about the possibility of overheating. A few times, I pointed the vents out the window and blasted the heat on full blast, but it didn't do anything to change the ambient temp.

After I finally got through the crossing (after 13 hours of waiting), and I started moving again, ambient temps dropped back down to normal (which was a beautiful 76').

Is it normal to read such high ambient temps? Is ambient temp related at all to coolant temps? Is there anything I could have done differently to reduce those temps?

I was so stressed out and tired from the wait and on top of that, I was worried about possibly overheating.
 


Dpro

6000 Post Club
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Location
Los Feliz (In the City of Angels)
#2
Your car is metal, It absorbs heat and sitting in the Sunlight will cause it to get really warm in fact it will raise the ambient temp reading on your dash. I have seen mine read 100 degrees when it is only actually 85-90 out routinely when my car is parked in the sun. It will not cause your car to over heat as your cooling fan is pulling air from outside the area that your ambient temp sensor resides and your ambient temp sensor is for outside temp not coolant temp. Thats the job of the idiot gauge and the coolant temp readout on your AP.
I also plan on getting a coolant temp gauge as it would be nice to have one in the cabin besides the idiot light or my AP
 


OP
SrsBsns

SrsBsns

Active member
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Location
San Diego
Thread Starter #3
Yeah, I know that the temps under the hood would be significantly higher than the actual environment, but I was looking at a ~30' difference. I would have been fine if it were in the 5-10' range, but +30 was making me super nervous.

I figured the fan was doing its job, but I'm guessing I had my coolant temps around 200' for quite a while since I was just idling forever.
 


Messages
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60
Location
So Cal
#4
Mine has done that while just sitting, seen as much as a 25* difference, but no overheating even in heavy traffic.
Also 13 hours? o_O
 


OP
SrsBsns

SrsBsns

Active member
Messages
657
Likes
695
Location
San Diego
Thread Starter #5
Mine has done that while just sitting, seen as much as a 25* difference, but no overheating even in heavy traffic.
Also 13 hours? o_O
I feel better to know that it's normal. Thanks.

And yeah, 13 hours. It was a nightmare. And one of the worst parts is that nobody seems to know why. TSA guy hit me with the "sometimes it be like that."
 


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Location
San Jose
#6
I mean 200 F for coolant isn’t that bad. The cooling system self pressurizes which actually raises the boiling point of your coolant. Considering water boils at 212 F, 200 F shouldn’t be too bad at all.


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