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Location of Intake Air Temp and Ambient Air Temp sensors?

iso100

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#1
I'm noticing that the outside air temperature as shown in the gauge cluster is different (usually a few degrees colder) than what's shown as the Ambient Air Temp in the accessport monitor.

This leads me to believe that it's a separate sensor. Anyone know where each of these are?

I know there's one in the driver's side of the cowl that directs air from the upper grille to the radiator... but I'm not sure if this is ambient or if this is the one that's used to show the outside temp in the gauges.

I know that Intake Air Temp is measured in the MAF sensor.
 


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iso100

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Thread Starter #3
We sure do. The ECU for US tuning doesn't use the MAF signal but it uses the IAT for temperature readings. It's mounted right in the cover of the factory airbox.
 


DHM1

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#4
I'm noticing that the outside air temperature as shown in the gauge cluster is different (usually a few degrees colder) than what's shown as the Ambient Air Temp in the accessport monitor.

This leads me to believe that it's a separate sensor. Anyone know where each of these are?

I know there's one in the driver's side of the cowl that directs air from the upper grille to the radiator... but I'm not sure if this is ambient or if this is the one that's used to show the outside temp in the gauges.

I know that Intake Air Temp is measured in the MAF sensor.
Yup intake air is in the MAF and the Ambient is the sensor on the driver side of the from grill.

Russ
 


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iso100

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Thread Starter #5
Yup intake air is in the MAF and the Ambient is the sensor on the driver side of the from grill.
Thanks Russ. Any idea where the outside air temperature is coming from? It's the one that's in the gauge cluster and is always different than what I see on Ambient on the AP.
 


DHM1

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#6
Thanks Russ. Any idea where the outside air temperature is coming from? It's the one that's in the gauge cluster and is always different than what I see on Ambient on the AP.
Im not to sure. Normally at night I see them the same. I feel like the sun changes the out side temp.

Russ
 


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iso100

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Thread Starter #7
I really want to find this other unicorn sensor!
 


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#9
When I start my car after a complete cool-down, the COBB Ambient, COBB Intake Air, COBB Charge Air, and MyFordTouch are identical. When I get moving, the COBB Ambient will usually drop to 4-8 degrees cooler than MYFord Touch. COBB Intake Air will follow the MyFordTouch and COBB Charge Air will be 1-2 degrees higher than MyFordTouch when cruising. During hot idle at a stop light, the COBB Ambient can get as close as 2 degrees cooler than MyFord Touch, and COBB Intake Air & Cobb Charge Air go 10+ higher than MyFord Touch. Stock fmic, 3" plastic/aluminum intake with a closed filter box, radiator shroud opened before intake inlet like Mod Bargains article.
 


Sourskittle

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#11
I feel like it does some math and uses the Ambient sensor. We have some kind of "sun sensor" and a Light Sensor too.


Russ, if def does some kind of math. If I spray the sensor a few times over and over for about 90 seconds, the temp on my dash/sync will drop 3-4degrees on the same road because the charge temps are 10 degrees below abundant or so, and the car thinks "wtf is going on, that can't be possible for the intercooler to drop temps below what the intercooler is seeing", lol.

No idea on its logic.... But its not a straight up " X = X" type sensor.
 


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iso100

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Thread Starter #12
Over the weekend when the outside air temp said 89 in the gauges, the AP showed 65 for ambient air temp. Something is just not right.
 


BoostBumps

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#13
I asked Braden at Cobb about the differences typically seen between Ambient reading on AP verses "outside" temps which appears inside on the cluster..

Hopefully this helps clarify things...


"The Fiesta ST does not have an actual AAT sensor, so it relies on the ECU to "infer" temperature via algorithms in place that watch ECT, IAT, CAT, and VSS. There are setting in the ECU to infer this temperature at faster rates with less requirements, but typically it is still grossly inaccurate for anything in need of compensation.

To top this, the Fiesta ST instrument panel is not connected to the ECU along the same CANbus stream like the Focus ST. This means the inferred temperature is not shared with the IPC, and it derives a value on its own.

Next time you go for a drive after a long cool-down. Watch the rate at which the AAT monitor changes when you are traveling under 20mph, then accelerate above 22mph and compare."
 


serrj

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#14
I'm noticing that the outside air temperature as shown in the gauge cluster is different (usually a few degrees colder) than what's shown as the Ambient Air Temp in the accessport monitor.
This leads me to believe that it's a separate sensor. Anyone know where each of these are?
I know there's one in the driver's side of the cowl that directs air from the upper grille to the radiator... but I'm not sure if this is ambient or if this is the one that's used to show the outside temp in the gauges.
I know that Intake Air Temp is measured in the MAF sensor.
Hi!
Sorry for bumping an thread, but I have the same problem as TS :(
And in my case temperature difference is always 15-17 deg.! For exaplmple is outside tempeature 15 Ā°C, it always shows ~31 Ā°C. And it doesnt matter if car is cold or warmend up, moving or idling: difference is linear and always the same.
I own an european version of ST, maybe it has AAT sensor somewhere? I also believe that this sensor has an influence on automatic climate control.
 


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#15
I hate to dig up a zombie thread myself, but in the last week my dash has been reading temperatures in the mid-50's, when I know that the outside temperature is closer to 80. Is this a sensor that I can easily replace myself? It's mostly just an annoyance, but I assume that my automatic climate control will be confused at the very least.


*edit* I'll try simply disconnecting the battery for a few minutes first, but if it continues to be a problem it would be nice to fix it if possible. I'm pretty much at the end of my warranty.
 


BronxBomber

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#16
[confused]nI'm having issues as well. After installing my Mishimoto cold air intake, my ambient air readings on my AP are all over the place. In he morning they are 10 degrees cooler than what the car is reading on the instrument cluster. As I drive aggressively the ambient air temp shoots up to 10-15 degrees above charge air which is impossible. This all coincided with changing my intake. Not sure what I could have screwed up. Car drives fine, but I know this isn't supposed to be like this and it's driving me nuts. When I had the stock air box with intake hose on, my ambient temps would always be about the same as my cluster outside temp reading. Something isn't right. Any ideas????[confused]
 


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#17
It's good to know I'm not alone on this. I routinely see a difference of anywhere from 5 to 15 degrees between ambient temps on my Accessport vs. the Sync display.

I know there's a TSB for recalibrating the climate control on my car (that doesn't work right either), so can't help but wonder if part of the recalibration is related to the wonky algorithm they use to calculate ambient air temp.
 


mishimoto1

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#18
[confused]nI'm having issues as well. After installing my Mishimoto cold air intake, my ambient air readings on my AP are all over the place. In he morning they are 10 degrees cooler than what the car is reading on the instrument cluster. As I drive aggressively the ambient air temp shoots up to 10-15 degrees above charge air which is impossible. This all coincided with changing my intake. Not sure what I could have screwed up. Car drives fine, but I know this isn't supposed to be like this and it's driving me nuts. When I had the stock air box with intake hose on, my ambient temps would always be about the same as my cluster outside temp reading. Something isn't right. Any ideas????[confused]
Hey Guys,

Thank you for the post.

I apologize that you are having issues with your intake, but we will be happy to work with you on a resolution.

At your earliest convenience, please contact us at Support@Mishimoto.com.

Best Regards,
Mishimoto
 


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