High RPM when engine starts (NEW 2017 CX5)

I know it's normal, but I wonder how good this is for the engine in <30 degree temperatures before oil has a chance to circulate and recoat the engine properly.

Modern oils for winter use (and specially the 0w-20 that mazda uses in CX-5 or perhaps even CX-3) do not need to be warm to circulate. They are already very fluid enough to circulate, so just start and drive away. I am surprised that some motoring schools in USA still tell students to start the engine and wait for few minutes before driving off (very unnecessary, and very polluting and very old fashioned when the oils were not really multigrade and thin). We drive cars in minus 30 degrees C sometimes here in Sweden and the instructions from the car makers and driving schools is that, you just start and go. Of course for the first few minutes there is going to be some pollution because of cold engine and partially burnt gases but the engine under load warms up quickly and emissions come down. And you have travelled a distance in that time instead of sitting in the drive way and polluting the world.
In the northern Sweden where the winters are long and intense people use electrical engine heaters (combined often with coupe heater) on timer so that there is even less pollution on start and you get to sit in a warm car.
 
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So I got an oil change today and they tried to tell me I need to pay $219.00 for an intake cleaning to improve my gas mileage. My gas mileage has been averaging 25mpg since I bought the car, now with 60,000 miles on it so I declined.

May be steep or may be cheap. Depends on what is entailed. that said I'm still waiting for someone to seafoam their skyactiv and post results :)
 
So I got an oil change today and they tried to tell me I need to pay $219.00 for an intake cleaning to improve my gas mileage. My gas mileage has been averaging 25mpg since I bought the car, now with 60,000 miles on it so I declined.
If I'm not mistaken, by "intake cleaning" I think they meant taking off the intake manifold and cleaning the valves. It is a worthwhile thing to do on direct injection engines to get rid of carbon deposits. In which case, if you do not have the expertise to do it yourself, $219 doesn't seem so bad.
 
This engine revving at idle comes up quite often. It only occurs under certain condition so I think the best thing is a PDF!
 
This engine revving at idle comes up quite often. It only occurs under certain condition so I think the best thing is a PDF!

<Operating Requirement>
1. Water temperature (ECT) at engine starting: from 15 to 32 degrees Celsius.
Intake air temperature (IAT) at engine start: from 15 to 35 degrees Celsius.
Barometric pressure at (BARO) at engine start: from: 91 to 200 kPa.
2. Gear position: P, N, D with the engine idling (Accelerator pedal not depressed)

Looks like the emissions test is done between 15C and 32C in Europe?
At least they aren't hiding it unlike a certain German brand.
 
Looks like the emissions test is done between 15C and 32C in Europe?
At least they aren't hiding it unlike a certain German brand.

No I don't think it's linked to an emmision test, it's because it doesn't need to behave that way outside of the parameters due to the chemistry involved. I'm not a chemist but that's how I read the bulletin. I think Mazda are utterly ethical in their business.
 
No I don't think it's linked to an emmision test, it's because it doesn't need to behave that way outside of the parameters due to the chemistry involved. I'm not a chemist but that's how I read the bulletin. I think Mazda are utterly ethical in their business.

I'm not saying they are unethical (the vw analogy was maybe out of place).

All car makers make compromises in their cars to pass the emissions tests and they have done so as long as the tests have been around.
If the test is done at 15C-32C than the car will be designed to be as clean as possible in that range, even if that means doing things that might lower durability or fuel economy.

Whatever special heating of the catalytic converter is required at 15C-32C would also be required below 15C, but for some technical reason it's not done at lower temperatures. Maybe the engine would stall if the special heating was attempted? or maybe the procedure reduces the service life of the cat? Or maybe there is a whole other catalyst heating procedure that runs under 15C that I don't know about and I'm completely wrong.
 
I'm not saying they are unethical (the vw analogy was maybe out of place).

All car makers make compromises in their cars to pass the emissions tests and they have done so as long as the tests have been around.
If the test is done at 15C-32C than the car will be designed to be as clean as possible in that range, even if that means doing things that might lower durability or fuel economy.

Whatever special heating of the catalytic converter is required at 15C-32C would also be required below 15C, but for some technical reason it's not done at lower temperatures. Maybe the engine would stall if the special heating was attempted? or maybe the procedure reduces the service life of the cat? Or maybe there is a whole other catalyst heating procedure that runs under 15C that I don't know about and I'm completely wrong.

Sorry, I wasn't suggesting you meant it was unethical, I was agreeing with you! I know on gasoline engines they pass the fuel vapours through a carbon filter (to reduce hydrocarbons I think) but only it low temperature and it switches off as it warms up. Maybe one of the boffins will know :)
 
So I got an oil change today and they tried to tell me I need to pay $219.00 for an intake cleaning to improve my gas mileage. My gas mileage has been averaging 25mpg since I bought the car, now with 60,000 miles on it so I declined.

Intake cleaning is a real thing for DI motors and very useful.

$220 for a full intake clean is a very good deal

60k Miles is around when you what to have them cleaned

Your engine will get better MPG, run smoother and sound better

May be steep or may be cheap. Depends on what is entailed. that said I'm still waiting for someone to seafoam their skyactiv and post results :)

Its best to take off the intake manifold and just clean everything out. Sea foam isnt effective for this.

If I'm not mistaken, by "intake cleaning" I think they meant taking off the intake manifold and cleaning the valves. It is a worthwhile thing to do on direct injection engines to get rid of carbon deposits. In which case, if you do not have the expertise to do it yourself, $219 doesn't seem so bad.

Yes, thats honestly a good deal for the amount of work required. My engine is already showing signs of carbon buildup at only 50k miles.

You can slow the buildup of carbon by doing a slow, smooth pull to redline roughly once a week and changing the oil more often.

If you drive at Low RPM for an extended period of time without giving the engine a chance to breathe, the carbon will accumulate faster and begin to buildup in the exhaust system. At this point, doing 2-3 full throttle pulls in a row will result in a very smelly exhaust as you are clearing out the carbon. Engine will run smoother afterwards. If you do this regularly, you will not need a walnut blast/intake clean so soon.
 
Intake cleaning is a real thing for DI motors and very useful.

$220 for a full intake clean is a very good deal

60k Miles is around when you what to have them cleaned

Your engine will get better MPG, run smoother and sound better

My MPG has not changed since I bought my car. I would not expect it to get any better with a 2 hour dealer intake cleaning. Dealer told me they don't take off the manifold, just run a 2 hour chemical concoction through the motor. Sounds fishy to me. There was no data provided stating I need it other than the car has 60,000 on it? I have run many direct injection cars well over 100,000 miles and never had a reduction in MPG. Maybe it's because I beat the snot out of them!



It’s best to take off the intake manifold and just clean everything out. Sea foam isn’t effective for this.



Yes, that’s honestly a good deal for the amount of work required. My engine is already showing signs of carbon buildup at only 50k miles.

You can slow the buildup of carbon by doing a slow, smooth pull to redline roughly once a week and changing the oil more often.

If you drive at Low RPM for an extended period of time without giving the engine a chance to breathe, the carbon will accumulate faster and begin to buildup in the exhaust system. At this point, doing 2-3 full throttle pulls in a row will result in a very smelly exhaust as you are clearing out the carbon. Engine will run smoother afterwards. If you do this regularly, you will not need a walnut blast/intake clean so soon.
 
So I got an oil change today and they tried to tell me I need to pay $219.00 for an intake cleaning to improve my gas mileage. My gas mileage has been averaging 25mpg since I bought the car, now with 60,000 miles on it so I declined.

Good decision. Probably were going to add some $ 5.00 injectors cleaners to the gas tank and that is it or maybe do some "italian tune up" [emoji23][emoji23][emoji23]
 
So I got an oil change today and they tried to tell me I need to pay $219.00 for an intake cleaning to improve my gas mileage. My gas mileage has been averaging 25mpg since I bought the car, now with 60,000 miles on it so I declined.

Unless they remove your manifold and physically clean the valves, its good you declined.

Intake port buildup for direct injection motors is a real issue, but only for those who do not regularly rev the motor to redline. Failure to do this a few times a month allows too much carbon to build up. Our 2.5L with only 50k miles on the odo is already showing signs

Good decision. Probably were going to add some $ 5.00 injectors cleaners to the gas tank and that is it or maybe do some "italian tune up" [emoji23][emoji23][emoji23]

Thats exactly what they wouldve done.
 
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