2016-2018 Active Grille Shutters

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2018 CX9 GT Titanium Flash, had 2009 CX9 GT Copper Red Mica
I was having a look behind the grille of my 2018 GT, noticed in front of the radiator a shutter assembly. I was trying to put a screen in front to keep bugs and fuzz sticking to the rad fins. I know the 3 and 6 had them on certain models. Can anyone confirm they are active on a CX9 and how you can check they are working?

I found a PN of the shutter BJD650R10.
 

sm1ke

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Canada
:
'18 CX-9 Signature
I remembered this post today, so after my drive in to work I decided to see if it was tied to the HVAC controls. My thinking is that the shutters would stay open until you enable recirculation on the HVAC system. I put the car in park with the HVAC settings as shown below (top):


PhotoGrid_1534856248861.jpg

Then I went to take a look at the shutters. They were closed. I then switched the HVAC to the settings above (bottom). Still closed. I turned off the car, and they were open. I wonder if they are tied into the thermostat, and only open when the engine reaches operating temp? Or is it tied into the vehicle speed or external temps?

Tested on a 2018 Sig.
 
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‘17 CX9 Sig/ ‘19 6
From reading on other cars the shutters close for aerodynamics unless airflow for cooling is needed.
My Escape and prev Fusion hybrid had active grille shutters. They activate when cruising on the highway for aerodynamic purposes (to reduce drag) but open when on slower speeds...has nothing to do with helping cool down engine or warm it faster
 
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2018 CX9 GT Titanium Flash, had 2009 CX9 GT Copper Red Mica
Well not sure at what outside temp it is triggered at but today I started my 9 and it was 3C on the OAT gauge and the shutters were closed. Once the vehicle temp gauge got out of the blue range and the blue light went out the shutters went open. So, the shutters definitely aid in allowing the engine to warm up quicker. Not sure if they are used at any other times, as it gets more into winter I'd be interested to see will also close when it's really cold and the heater is on full hot. Mazda doesn't advertise that the CX9 has active grill shutters for fuel saving like they did on the 3 and 6. I'd have to put a camera behind the grill and go for a drive to see if at any other time they move.
 
They are used for both faster warm up and for fuel economy purposes. Couple things to note:

1. Warmer air into the intake increases fuel economy, but reduces peak power due to lower air density. To maintain stoic, warmer air (less dense) requires less fuel (Air / fuel ratio). The cooler the air, the more fuel is needed to maintain full burn and more air / fuel density = greater power output to a certain point. Back when I had my Mustang Ecoboost 2.3L (350 HP) and later Mustang GT V8 (480 HP) it was common for those cars to run 0.2 to 0.5 seconds faster on a 1/4 mile just between the hottest part of the day and the cool of the evening because of air density and humidity changes. If you noticed the snorkel for the intake of the SkyActive-G 2.5T is at the top of the engine bay where the hottest air is...because heat rises, unlike my Mustang GT where the ram air intake was lower down on the bumper and fed mildly pressurized cool air in right from outside the car. This aids in fuel economy while cruising in a low power state. Honda is going so far as to actually heat the air going into the intake with a heater element for better fuel economy...

2. Aero dynamics as mentioned by another poster. Closing off the front of the grille reduces drag as the air entering the engine compartment has to move past many very non-aerodynamic components. On a performance car, you actually vent the hood itself to get better air flow through the radiator (look at the GT350 hoods for example with the large center vent, it's purpose is to allow a direct air flow path from the front of the radiator directly past it to increase air flow for cooling). But on a daily driver, your more concerned about fuel economy than cooling the car for sustained high RPM uses.

3. Faster warm up which was also mentioned. By choking off flow, you can build up heat in the engine faster as your not transferring heat from the radiator core to the ambient air (or not as much). While the thermostat regulates coolant flow rates weather the shudders are open or closed, it cannot by nature allow circulation of the coolant AND fast heat buildup if air is flowing past the radiator. In order to fully heat all of the coolant, you need to circulate it, but not transfer heat to the ambient air. Choking off air flow to the radiator allows all of the coolant to warm up (as heat builds up in the block, pressure is built up and the thermostat opens and begins to circulate coolant).

Notice that the inter cooler does NOT have grill shudders. It's 100% open and exposed 247. We wouldn't want to choke off flow to the FMIC because extremely hot air will cause heavy knocking or detonation and consequently crack a land / groove in the piston or bend a rod. We always want the inter cooler to bring the charge temp down as close to ambient as possible. But when cruising at low loads, the turbo goes into bypass and just free spools and the engine operates as a NA (non turbo engine) where the greatest fuel economy is achieved. When in boost, your always going to consume substantially more fuel because air density is much higher and your only going to go into boost when there's a demand for a lot of torque.

When I had my 2016 Mustang Ecoboost, I had removed the active grill shudders to fit a full sized inter cooler as I was tracking the car. I can say for certain that warm up times were noticeably longer as I was able to monitor my oil temps via OBDIILinkMX and TorquePro app (later was able to do it through Ford Performance ProCal once I upgraded to their Power Pack). However I did not notice any drop in fuel economy, but the Ford Performance calibration was more aggressive with fueling (leaner) than the factory Ford calibration, so that may have off-set some of the losses.
 
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sm1ke

Work In Progress..
Moderator
Contributor
:
Canada
:
'18 CX-9 Signature
They are used for both faster warm up and for fuel economy purposes. Couple things to note:

1. Warmer air into the intake increases fuel economy, but reduces peak power due to lower air density. To maintain stoic, warmer air (less dense) requires less fuel (Air / fuel ratio). The cooler the air, the more fuel is needed to maintain full burn and more air / fuel density = greater power output to a certain point. Back when I had my Mustang Ecoboost 2.3L (350 HP) and later Mustang GT V8 (480 HP) it was common for those cars to run 0.2 to 0.5 seconds faster on a 1/4 mile just between the hottest part of the day and the cool of the evening because of air density and humidity changes. If you noticed the snorkel for the intake of the SkyActive-G 2.5T is at the top of the engine bay where the hottest air is...because heat rises, unlike my Mustang GT where the ram air intake was lower down on the bumper and fed mildly pressurized cool air in right from outside the car. This aids in fuel economy while cruising in a low power state. Honda is going so far as to actually heat the air going into the intake with a heater element for better fuel economy...

2. Aero dynamics as mentioned by another poster. Closing off the front of the grille reduces drag as the air entering the engine compartment has to move past many very non-aerodynamic components. On a performance car, you actually vent the hood itself to get better air flow through the radiator (look at the GT350 hoods for example with the large center vent, it's purpose is to allow a direct air flow path from the front of the radiator directly past it to increase air flow for cooling). But on a daily driver, your more concerned about fuel economy than cooling the car for sustained high RPM uses.

3. Faster warm up which was also mentioned. By choking off flow, you can build up heat in the engine faster as your not transferring heat from the radiator core to the ambient air (or not as much). While the thermostat regulates coolant flow rates weather the shudders are open or closed, it cannot by nature allow circulation of the coolant AND fast heat buildup if air is flowing past the radiator. In order to fully heat all of the coolant, you need to circulate it, but not transfer heat to the ambient air. Choking off air flow to the radiator allows all of the coolant to warm up (as heat builds up in the block, pressure is built up and the thermostat opens and begins to circulate coolant).

Notice that the inter cooler does NOT have grill shudders. It's 100% open and exposed 247. We wouldn't want to choke off flow to the FMIC because extremely hot air will cause heavy knocking or detonation and consequently crack a land / groove in the piston or bend a rod. We always want the inter cooler to bring the charge temp down as close to ambient as possible. But when cruising at low loads, the turbo goes into bypass and just free spools and the engine operates as a NA (non turbo engine) where the greatest fuel economy is achieved. When in boost, your always going to consume substantially more fuel because air density is much higher and your only going to go into boost when there's a demand for a lot of torque.

When I had my 2016 Mustang Ecoboost, I had removed the active grill shudders to fit a full sized inter cooler as I was tracking the car. I can say for certain that warm up times were noticeably longer as I was able to monitor my oil temps via OBDIILinkMX and TorquePro app (later was able to do it through Ford Performance ProCal once I upgraded to their Power Pack). However I did not notice any drop in fuel economy, but the Ford Performance calibration was more aggressive with fueling (leaner) than the factory Ford calibration, so that may have off-set some of the losses.
Wow. Very helpful post, chock full of useful information. Thanks!
 
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Mazda CX-9 Grand Touring 2016
And...a cold engine requires a richer gas/air mixture. Faster engine warming reduces gasoline consumption and yields cleaner exhaust.
 
Found out from Mazda documents exactly how the active grill shutter on the CX-9 works and its purpose. It pretty much confirms much of the assumptions made above. According to Mazda, the active air shutter:

- reduces air resistance
- allows the engine to warm up more efficiently.

From Mazda: "By reducing the air resistance and improving the engine warm-up efficiency, the fuel economy has been improved."

The info above was kind of a given, but the interesting part to me was how it operates exactly. The active grill shutter has 3 positions: 0 degree (closed), 78 degree open, and 90 degree (fully opened). The three positions are used under the following conditions:

Fully closed
- when all the following conditions are met:
a. Vehicle speed: less than 140 km/h {87.0 mph}
b. Engine coolant temperature: less than 100 °C {212 °F}
c. Load condition due to A/C operation: vehicle speed and refrigerant pressure during A/C operation are the specified values or less
d. Protection control is not operating


78 degree open (according to Mazda this position allows more airflow to the radiator than when fully opened).
- when any of these conditions are met
a. Vehicle speed: 140 km/h {87.0 mph} or more
b. Engine coolant temperature: 100 °C {212 °F} or more
c. A/C operation is in the following range (to cool the condenser): (Mazda provides a graph here), but it is basically when the vehicle speed is below 85km/h (53 mph) and the refrigerant pressure is above 1.7 MPA
- when protection control is active, the active grill shutter remains open until ignition is switched off:
a. Engine coolant temperature: 116 °C {241 °F} or more; or
b. If the car PCM receive a cooling fan request signal from the transmission.


Fully opened
- when engine is turned off
- during the position learning sequence (initialization at every startup once vehicle reaches 10km/h (6.2mph)


So there it is, and as from the suggestions that it might be used for warmer air intake (as per TheLion's post earlier), it does not seem to be the intent from Mazda. And that make sense because the CX-9 as a stock cold air intake and the active grille shutter is not in the air path of the air intake. The snorkel in the engine bay is at the top like TheLion mentioned, but it is sealed off from the engine bay when the hood is closed and gather it's air from the front of the vehicle.
 
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