Mazda 6 - Poor mpg on Mazda 6 2.0 petrol

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Wed 29 Mar 2017 12:22
Mazda 6 - Poor mpg on Mazda 6 2.0 petrol - Pietrach

Hi

Few months ago I purchased a 2011 mazda 6 2.0 petrol (takuya trim). The average mpg on the computer was shown as 34 if I remember well, and the owner was using the car for a daily commute on motorways of around 30min each way.

I expected the mpg to rise as I use the car on very short trips only up to 3 miles, and ocassionally a long trip of say 100 miles once a month. I thought this would probably drop to say 30mpg which is something I can live with.

Well the first two tanks I got worried as I thought these did not last too long. But I havent calculated anything. An the computer dropped to 30mpg.

I then did calcs on next tank and it resulted in 24mpg! The current tank is getting to an end and it looks slightly better, but I had a higher proportion of longer trips this month.

Based on my observations, on motorways I am getting around 34mpg, but urban drops to 24mpg.

Is this normal, or should I investigate? If so, how do you go about this? Should I just ask my local garage for some sort of check?

Thank you

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Wed 29 Mar 2017 12:25
Mazda 6 - Poor mpg on Mazda 6 2.0 petrol - skidpan

2 litre

big(ish)

old(ish) school petrol

3 mile trips

Winter

24 mpg sounds good to me.

Edited by skidpan on 29/03/2017 at 12:25

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Wed 29 Mar 2017 12:30
Mazda 6 - Poor mpg on Mazda 6 2.0 petrol - RobJP

It sounds about right.

Very short trips of 3 miles or less, the engine isn't warming up until the journey is virtually over. Fuel economy in such a case will be horrible.

Do also remember that fuel economy is generally worse in winter too.

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Wed 29 Mar 2017 13:12
Mazda 6 - Poor mpg on Mazda 6 2.0 petrol - SLO76
Big petrol engines car and mostly short stop start driving do not a good combination make regards fuel economy but when I used our 58 plate 2.0 petrol 6 for mostly local runs it was doing over 30mpg and would touch 40mpg easy enough on longer runs. In fact I was pleasantly surprised by the economy.

Has the car been frequently serviced? Has the fuel filter ever been changed? Possibly a sticky brake calipper which is pretty common on older Mazda's though I'd be surprised at this age. Even the tracking being out of Alignment can hurt economy by a few mpg. Unless your driving style is at fault or your mpg calculations are wrong I'd say there's a problem of some sort.
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Wed 29 Mar 2017 13:21
Mazda 6 - Poor mpg on Mazda 6 2.0 petrol - Pietrach

Thank you.

I am extra carefull with my driving style and if not economic driver then definitelly not worst than average. I car has the full service history, but before the measurements I have done the full service with fuids and filters changed. Also the hand brake was fixed (which was very poor) and the rear calipers replaced.

I will carry on with measurements to get more meaningfull averages and then mention this to my garage on the next servise.

But any more experiences / opinions would be very useful.

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Wed 29 Mar 2017 22:35
Mazda 6 - Poor mpg on Mazda 6 2.0 petrol - kiss (keep it simple)

That sounds a bit heavy on the juice if my experience is anything to go by. I have a 2012 2.0l model (last of the mk2) and the car managed on average 38 for the last few thousand miles since i bought it. The computer is quite accurate as verified by brim to brim tankfuls. One interesting exercise is to re-set the computer just before a short journey. You will be shocked! I recently did a gentle M25 run of about 50 miles (busy traffic kept speed down) and managed 47mpg. It's not that much of an old-school engine, it does have direct injection which makes it a bit better than my last Mazda 6.

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Tue 2 Jul 2019 16:18
Mazda 6 - Poor mpg on Mazda 6 2.0 petrol - Andrec

Hi. Sorry to resurrect an old thread but I am having exactly the same issue with the same car, same spec. Did you ever get this resolved? Thanks.

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Thu 4 Jul 2019 20:26
Mazda 6 - Poor mpg on Mazda 6 2.0 petrol - Paul McGinness
My Mazda 6 tourer 2013 diesel, 65,000 on clock has just been recalled for the following issues DIESEL ENGINE CONCERNS whereby the following was carried out: Revised fuel injector tighten, replaced vacuum pump and carried out software update. Within days and very little use/mileage there was an issue with turbo kicking in affecting acceleration in each gear, and warning lights for : SCBS INSPECTION REQUIRED and ENGINE INSPECTION REQUIRED. A vehicle health check was also carried out whereby NO issues or concerns were raised other than worn pads/discs and tyres to be changed in near future.

This has now been back into the Mazda dealership to investigate. They have informed me that Turbo is gone and requires replacing at an estimated cost of £2k plus. After being in for recalls the car was used a handful of times and minimal mileage, can anyone advise whether this recall and then the subsequent problem could be linked? I’m more than a little bit cynical and questioning the fact that we have never had issues with the engine or turbo in anyway up until now and almost immediately after it’s been in and they have been in about injectors and pumps that there is now this issue. I’m not machanically minded so have no idea if this could be the case. Any advice would be appreciated.

The dealership/garage has taken a considerable time to get back to me with a quote having stated they need to contact Mazda itself, and they were also asking whether I have full service history (which I do) and is making me more suspicious they are trying to get out of something that may well be their fault/blame.

Thanks in advance
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Thu 4 Jul 2019 22:12
Mazda 6 - Poor mpg on Mazda 6 2.0 petrol - Heidfirst

Andrec, if you are also doing 3 mile trips then as others said earlier in the thread it seems about right. The engine from a cold start will run rich & will never really have a chance to reach normal operating temperature.

Edited by Heidfirst on 04/07/2019 at 22:13

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Fri 5 Jul 2019 05:57
Mazda 6 - Poor mpg on Mazda 6 2.0 petrol - KenC

3 mile trips means the engine never reaches optimum efficent temperture, town driving always uses more fuel, maybe a smaller engine car would have been a better choice for short journeys

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