Best way to warm engine in morning when colder temp [0-31°F]

[AL Cx5]

Racecar on Meth(anol) =

Operating Temp: Good point on all the other parts. Obviously engine and transmission are the big hitters, but all the other little things between the road and the engine impact FE.

Heater Core: I guess it depends on the vehicle. I know my 89 Mustang (yes, old) has the heater core bypass before the thermostat, so it's pumping coolant through the heater core all the time, regardless of thermostat position. Not sure on newer cars if they block off heater core as well during warmup. In any case, the size of the heater core is tiny compared to the actual coolant radiator, so the impact to warmup speed is minimal.

Also, while on the topic of fuel efficiency, don't forget the other features that 'suck power' like HVAC fan blasting full speed, heated seats/steering wheel, rear window and side mirror defrost. Those add electrical load and reduce FE as well.

The engine may be a little bit slower to warm up with the heater fan on. Maybe someone will drive one morning without the fan and not how long it takes for the engine to warm and repeat the next day and run the heater fan.

Since the the T Stat is closed, my guess it won't be much difference.

I normally turn the heater fan off until I see the temp above 130 F.

 

[AL Cx5]

The OP asked for the best way to warm up.

A standard and proven way is to warm the engine coolant with a block heater. Passengers have heat quickly and more important, engine clearances are larger. Oil warms quicker circulating through the warmed block.

I'm not saying the other methods don't work, preheating is the best.

I ordered a Mazda block heater kit and will install soon.

 

[AL Cx5]

The oil filter bypasses the oil until the oil viscosity/oil pressure drops. This is the worst time not to have oil filtration when the clearances are tight and metal is introduced into the oil.

I preheat my diesel year round when time permits. Better FE and less wear on the engine. 270k mi on the engine. Other than removing the valve cover, it's never been opened up. Does not use any oil between 10K mi oil changes.

We will start preheating the CX 5 as soon as I get the engine block heater installed...

 

[Lazy2.5]

As mentioned above, if you have an engine block heater, that is the single best way to warm up the car.

If not: When you start your car, once the ideal initially drops and settles, the car is ready to go. this does not take longer than 30 seconds.

drive gently until the blue coolant light is gone.

 

[AL Cx5]

When you start your car, once the ideal initially drops and settles, the car is ready to go. this does not take longer than 30 seconds.

the best way to warm up the car is to put it in gear and drive gently until the blue coolant light is gone.

I agree if one hasn't installed a block heater.

With block heater: Heat engine 1 to 2 hours before starting. Gently drive until ECT is near normal.

As an aside, I've experimented with closing up the front grill 30 to 50% in the winter on my 09 Accord. It warmed up much quicker and got better FE. I did the same on a friends Nisan. Same deal. We put grill covers on our Cummins diesel in the winter for quicker warm up and better FE. Below 50F I use a radiator winter cover on the diesel that has flaps to adjust air flow. Again, quicker warm up and better FE.

I might experiment with grill covers on the CX 5 in the future. For now, get the block heater installed is top of the list.

 

[sm1ke]

I agree if one hasn't installed a block heater.

With block heater: Heat engine 1 to 2 hours before starting. Gently drive until ECT is near normal.

As an aside, I've experimented with closing up the front grill 30 to 50% in the winter on my 09 Accord. It warmed up much quicker and got better FE. I did the same on a friends Nisan. Same deal. We put grill covers on our Cummins diesel in the winter for quicker warm up and better FE. Below 50F I use a radiator winter cover on the diesel that has flaps to adjust air flow. Again, quicker warm up and better FE.

I might experiment with grill covers on the CX 5 in the future. For now, get the block heater installed is top of the list.

I don't know for sure on the 24 CX-5s, but some of them have motorized grill shutters that open and close automatically to help the car warm up in the winter and keep the car cool in the summer.

A block heater is a must for me in central Canada. Mine was dealer-installed and made by Temro. I like this one because the block heater cord disconnects at a connector in the lower grille, and when it's not in use, it's covered by a small cap. Really clean installation.

 

[AL Cx5]

I don't know for sure on the 24 CX-5s, but some of them have motorized grill shutters that open and close automatically to help the car warm up in the winter and keep the car cool in the summer.

A block heater is a must for me in central Canada. Mine was dealer-installed and made by Temro. I like this one because the block heater cord disconnects at a connector in the lower grille, and when it's not in use, it's covered by a small cap. Really clean installation.

View attachment 333078

My 24 doesn't have auto grill door feature. I wonder why Mazda dropped this on my 24 CX 5 T.

That's clean install. I might look into adding a cap on my 24. If one is OCD, pre heating year round improves FE and engine life. Thanks for the pic! Is that white stuff sand?

I'll get started on it next week. I'm waiting of a gal of concentrate coolant to arrive.

 

[sm1ke]

Is that white stuff sand?

Naw that's just road grime. It warmed up a bit today so the icy roads were a bit wet on my way in.

 

[AL Cx5]

I don't know for sure on the 24 CX-5s, but some of them have motorized grill shutters that open and close automatically to help the car warm up in the winter and keep the car cool in the summer.

A block heater is a must for me in central Canada. Mine was dealer-installed and made by Temro. I like this one because the block heater cord disconnects at a connector in the lower grille, and when it's not in use, it's covered by a small cap. Really clean installation.

View attachment 333078

How long do you let the block heater run before you drive you car?

I put my truck on a timer and allow 1.5 to 2 hours before driving.

 

[sm1ke]

It depends on how cold it is. I've just left it on overnight during really cold snaps (like -40 to -50c with the windchill), but normally its about 3 hours before driving at least.