2014 CX5 2.5 fuel econ horrible
- Thread starter VanguardX
- Start date
Fill slower once you reach the 10-12 gallon mark and you won't have this issue as dramatically.
donkeykong
Member
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- 2014 Mazda CX-5 FWD w/ Tech
According to some posts above, there should be ~50 miles (2 gallons) left when the range meter gets to 0. I wasn't concerned.
Thanks, I did follow your tip this time but it didn't seem to help. Kind of troubling that it says it's full but you can really put up to 3 additional gallons after that. Will bring it up to the dealer...
Chris_Top_Her
Contributor
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- San Antonio, Texas
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- '15 CX-5 Miata AWD
johnny_boy02
Member
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- Mazda CX-5 Touring
I have friends that are mechanics as well and they all disagee and say with a modern car the 1/4 tank urban legend is ridiculous. Fuel flowing through the pump cools it. No vehicle engineer is going to design a part that will fail when used under normal conditions then tell their customers "welp, shoulda kept'er above 1/4 tank cause I designed that pump to be sub-par!".
Believe anything you want but spreading misinformation does a disservice to others.
Typical fuel injected cars have around 80psi $70 fuel pump. An 80psi pump won't be hurt running dry.
The direct injected CX-5 runs a 150psi $150 in-tank pump into a 1000psi $600 fuel pump. The 1000psi fuel pump would most likely be damaged if it ran dry. At $600, I'll make sure I never run low on gas in the CX-5.
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I guess it depends on what you mean by 'hurt'. All fuel pumps I'm familiar with have impelloers that are lubricated with the fuel flowing through them. Running them dry will cause rapid wear on the contact areas of the impeller. They are not designed to be run without fuel in them.
I make sure I never run out of fuel. But running low is not a problem.
johnny_boy02
Member
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- Mazda CX-5 Touring
The issue was not "running a tank dry" it was someone telling mistruths about how your car will be damaged if it is run with a 1/4 tank of fuel or less.
A modern car will not be damaged if you frequently use 90+% of the fuel in your tank before refilling.
To go around telling people it is harmful to use more than 3/4's of a tank of fuel is ridiculous.
You know how to prevent from running out of gas? Fill up at 1/4 tank...
It's not rocket surgery!
You can't predict what's going to happen out on the road so give yourself some extra padding. It took me 6 hours to make a 2 hour trip once and I'm sure glad I wasn't already pushing the tank to empty. Granted that car wasn't direct injected but stranded is stranded.
It's not rocket surgery!
You can't predict what's going to happen out on the road so give yourself some extra padding. It took me 6 hours to make a 2 hour trip once and I'm sure glad I wasn't already pushing the tank to empty. Granted that car wasn't direct injected but stranded is stranded.
)Another method that is equally effective is to fill up any time before the pump starts sucking air.
For example, you will never run out of fuel if you always top off the tank every hour of driving. Or, if you always fill up when you have at least a quart of useable fuel left you will never run out of fuel. There is no hard and fast rule as to a fuel level that triggers a fuel-up as long as it is done before the pump sucks air. It really depends upon where you are going and what your schedule is. I've filled up a few times when I was only 1/2 - 2/3 empty because I knew I would otherwise need to drive out of my way to purchase fuel. It depends upon where you are going.
True, you always need some extra fuel for padding for the unexpected. The question under discussion is how much padding is needed to avoid running out of fuel. And that is different for each person and each circumstance. Obviously it makes no sense to fill up every time at 1/4 tank with over 100 miles remaining regardless of how many gas stations are on your route.
This is more true than ever with the exceptional idle efficiency of the CX-5 (in case of an unexpected traffic jam).
Because I track my MPG I am automatically alerted if a fuelling station pump shuts off before my tank is full. The giveaway is if my manually calculated MPG is more than one MPG higher than the MPG indicated on the trip computer. In that instance I will not push my range to the limit. But, with a tank filled to normal full there is always a couple of gallons left when the trip computer says "0 miles to empty". In my most common driving scenarios, that is all the buffer I need and I have no problem driving a few miles after it reads "0 miles to empty".
donkeykong
Member
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- 2014 Mazda CX-5 FWD w/ Tech
This is getting frustrating. I have now stopped overfilling my tank, and the calculated gas mileage based on odometer jumps to 29+ (great!), but I am having a very hard time believing this since the computer readout is still showing 25mpg. The 25mpg is consistent with the value I would get if I top off my tank another 2+ gallons like I was doing before.
I think it's time for a call to the dealer. I don't think it's normal that I can fill up another 2 gallons after the pump auto-shut off feature engages. From what I read about over-filling, it can cause damage to the car, but I really don't think I'm overfilling when there is TWO+ GALLONS of extra "capacity".
Can anyone verify how many gallons a typical fill up is for them, when you fill up at "0 miles to empty", and not over-fill after auto-shut off?
I think it's time for a call to the dealer. I don't think it's normal that I can fill up another 2 gallons after the pump auto-shut off feature engages. From what I read about over-filling, it can cause damage to the car, but I really don't think I'm overfilling when there is TWO+ GALLONS of extra "capacity".
Can anyone verify how many gallons a typical fill up is for them, when you fill up at "0 miles to empty", and not over-fill after auto-shut off?
Isn't 25MPG the EPA mileage? Not sure what you're so upset about. It's what I've been averaging with warmer weather and no snow to deal with.
Also, on board mileage is calculated by wheel rotation. It's really just a ball park way to monitor your driving habit and efficiency. Have you tried a GPS app to track your mileage? For some it can be off by a noticeable amount.
Also, on board mileage is calculated by wheel rotation. It's really just a ball park way to monitor your driving habit and efficiency. Have you tried a GPS app to track your mileage? For some it can be off by a noticeable amount.
it looks like some cx-5 engines performing well and others performing very bad. Mine 2014 2L is 13L/100Km now where as there are cx-5s with 9-10L/100Km on the same roads. Can it be the driving - I do not believe so, I drove very aggressively, quick startups, braking, overtaking, the average goes up by few points. Therefore I believe that there is some technical issue that Mazda has to solve for us.
You've got that in reverse, wheel mileage is pretty darn accurate unless you've changed the wheels. You can test it by doing an odometer run between mile markers.
donkeykong
Member
- :
- 2014 Mazda CX-5 FWD w/ Tech
I'm not upset about the actual number. I am just trying to make sense of the gross mismatch between measurement methods, and the fact that when I overfill the tank, it matches what the computer is saying. When I take the advice from this forum to not overfill, I get inflated MPG numbers. Which is correct?
Also, the fact that I can overfill by 2+ gallons, doesn't seem right. That's an extra ~50 miles of range per tank...
Pipemajor
Hoot Mon!
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- Minnesota
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- 2017 CX-5 GT AWD
Took delivery 05/24. First fillup 06/03 @ 327 miles (about an eighth of a tank indicated remaining). Stopped when the nozzle shut off (I've totally stopped trying to top off). Fuel used = 11.273g which computes to 29.01 mpg. Took delivery of the car w/3 miles on the odometer so the tank was filled at the dealership at that point. All in-town driving. Price was $3.599/gal but got a double coupon discount making the final price $3.459.
Will fill up again tonight because we had to make a run north and back - all freeway use. 2nd tank figures will be posted when I return home.
EDIT for 2nd tank: 28.39mpg on a ~300 mile freeway dash at 70mph.
Will fill up again tonight because we had to make a run north and back - all freeway use. 2nd tank figures will be posted when I return home.
EDIT for 2nd tank: 28.39mpg on a ~300 mile freeway dash at 70mph.
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I took delivery of my 2014 2.5 GT AWD at the end of February. Initially I was getting 11.8 L / 100 kms (19.93 MPG). I've since modified my driving habits (learning how to coast in gear, no heavy startups, no heavy braking, etc)....and now with the warmer weather....I've got it down to 10.4 L / 100 kms (22.62 MPG). Not a fantastic increase in mileage....but I'll take it. I still love the vehicle and I'm hoping my mileage will get better with time.
By the way, here is a website for conversion (L/100 KM to MPG):
http://www.convertworld.com/en/fuel-consumption/Liters+per+100+km.html
Bon
By the way, here is a website for conversion (L/100 KM to MPG):
http://www.convertworld.com/en/fuel-consumption/Liters+per+100+km.html
Bon
