Mazda 3 Forums UK

General Category => Mazda 3 => Topic started by: Berengaria on June 30, 2018, 05:02:04 PM

Title: Fastback Queries
Post by: Berengaria on June 30, 2018, 05:02:04 PM
Considering a 2014 onwards Mazda 3 Fastback 2.0 SE petrol and have a couple of questions:

What is the engine rpm at 70mph in top gear?

What is the typical real-life mpg in these cars on a motorway. What could I expect?

Can the dashboard touchscreen unit display be turned off when the audio is in use?

If the heating / ventilation controls were set to a/c off, heating off and the fresh air setting (i.e air coming in from outside) when the engine was last running, does it default to / remember these settings when you come to restart the car again?

(On cold fresh air setting, my current car always defaults back to the air recirculate button being on, which is really annoying to me; having to switch it off every time I use the car)


Title: Re: Fastback Queries
Post by: Engineer Andy on June 30, 2018, 07:34:03 PM
I can't comment about the other two (my test drives were in two different cars), but from what I gather, you can expect mid 40s for motorway type driving, assuimng you're not heavy footed with the gas pedal.  Check out Honest John's (Telegraph Motoring Agony Uncle and long time motoring journalist/dealer) 'Real mpg' page on his website (not the US .com website).  The aggregate mpg (average for all drivers and types of driving) for the latest 2.0 petrol is currently just under 43mpg (EU 'test' average 55mpg).  You might get very slightly more for the fastback than the hatch as (like my mk1 saloon) its a bit better from an aerodynamic perspective.
Title: Re: Fastback Queries
Post by: Tall333 on June 30, 2018, 08:54:14 PM
Our 2015 is an auto and I'm pretty sure the revs sit about 2500 at 70mph, maybe a little higher.  Ours does 35-40mpg on the daily commute but it's not difficult to achieve 50mpg on a decent run or with a light foot.
The infotainment screen can be blacked out/switched off but having never done it I've no idea if it would stay that way when you started the car again. I personally hate bright screens and dials/gauges and always set my dash to dim when the headlights are on.  The main background of the screen is black and I don't find it intrusive or annoying, even at night.  On occasions when the lights come on during the day the screen becomes a bit too dark but I can live with that (or turn the stalk knob to brighten it back up).  I'm pretty sure you can also set the screen to be backlit a set amount, but I'd think it would be too bright at night and too dark during the day, so I leave it at auto setting,
I can't say whether recirc mode would be on with the heater off since ours is always set to auto.  I find it quite efficient when left to do it's own thing (although it's too quick at selecting 'feet' mode).
Title: Re: Fastback Queries
Post by: Engineer Andy on July 25, 2018, 12:24:51 PM
I suspect that the A/C, if turned on to 'auto' (the best setting, as Tall333 says - let the car decide how it achieves the temperature you've set the dial to), the car will decide whether the air recirculator is on or off.  Not a chore just to press the switch to change that to on/off as required when you're travelling through a tunnel, in heavy traffic or past smelly farms etc when you don't want the outside air coming in.  In the current very hot conditions, if the car has been sitting in the sun or not been used for some time, the auto A/C setting will likely set the system to maximum output (i.e. not 'eco') and turn the air recircuator on to stop very hot outside air reducing system performance, which will speed up the time taken to cool the interior down.  Many people (including myself) prefer to lower all the windows when you first move off (up to 40mph) in that sitauion with the A/C off, as this will purge the hot air from the interior far quicker than using the A/C.