Poor City MPG

[Sky14FFH]

1 hour ago, charleslam said:

I also use my autoclimate control religiously, so AC always a pumping in the texas sun.  

Yeah that will lower your mpgs.  I just got a 47.2 mpg tank the highest since I got the non LRR Michellin tires.  I am really disappointed because the brochure advertised the Premier A/S as the next most fuel efficient tire they have.  But my mpgs have tanked by 6mpg.  I used to get 53 under very conservative driving in the summer without using a/c and have posted a picture of a 700+mpg tank I got once on the old Energy Savers.  Regretting changing them.

 

How do you do in the winter with balmy weather and not using heat or ac?

[MeeLee]

I'd have to agree that low city mpg is not a fuel injector cleaning issue, since 40% of city driving would be done on electric.

 

Then again, I also don't think low tire pressure is the culprit, since you actually get much lower mpg on the highway from low tire pressure, than in the city.

 

I think the issue is the way you drive the car, and how the car deals with switching between gasoline and electric.

If you accelerate on the gasoline engine, and brake for red lights, without ever getting to coast on electric, your mpg may be low.

 

My recommendation is to pulse and glide. Don't use eco mode. Just accelerate normally until you reach cruising speed of 35-45MPH (whatever it is). Then coast on electric, brake gently (Aim for at least 75% braking efficiency in the coach) when hitting a red light.

Doing this helped me gain 5 to 6MPG easily.

 

The car's switching logic, to switch between gas and electric, isn't too smart. It doesn't know when the most efficient time to switch is. You as a driver can manually switch, by blipping (or quickly releasing) the throttle for a second, and force the car to run on ice or electric.

 

Edited August 17, 2021 by MeeLee

[FSMa1]

As a former Ford Service Manager here's my 2 cents.

Many of the suggestions here are not necessary or applicable. For 20 years plus injectors and throttle bodies have a special coating on them to prevent buildup. It eventually wears off but you should not even begin to think about this possibility for at least 5 years or 100,000 miles. Furthermore if you use certain cleaners that are too caustic you can damage this coating and create the very problem you are trying to prevent.

Next, the suggestion of tire pressure and type is a reasonable one (especially pressure) but the type isn't going to reduce the mpg by 25%.... you're talking 1-4 mpg maybe.

AC usage won't even make 1 mpg difference unless there's a problem with excessive drag from the compressor. 

Some mentioned "top tier" fuel. I'm not sure exactly what is meant by that but I will caution you NEVER use octane level higher than is recommended by Ford for your car. 

The manufacturer tells you what to use for a good reason... stop thinking you're smarter than those who designed the car and set the guideline for recommended fuel. The car was designed for the octane rating that is recommended. If it says 87 then use 87. Changing octane causes the computer system to make adjustments to several things including timing and fuel mixture. Changing back may take 2 tanks full to undo what you've done and relearn.

The only thing within your control that might make a 25% reduction in mpg is if you have a heavy foot. Other than that, you have a problem. There seem to be enough complaints on these models to consult TSBs and Ford technicians.

[2014FordFusionSE]

On 3/26/2022 at 3:00 PM, FSMa1 said:

Some mentioned "top tier" fuel. I'm not sure exactly what is meant by that but I will caution you NEVER use octane level higher than is recommended by Ford for your car.

 

I believe they meant:

https://toptiergas.com/licensed-brands/

[MeeLee]

From my experience fueling and driving rideshare well over 100k miles, most gas station fuels have the exact same mpg numbers within 1 to 2mpg.

 

The ones that exceed is Shell (by 5%), and the one that lags is Chevron and Valero by -10% of the standard. I can only assume Chevron and Valero use more ethanol, and their gas definitely has more water coming out of the exhaust than any other. In other words, you pay for water.

 

As far as octane levels go, they make sense in high compression, or turbocharged vehicles, or vehicles that run in very hot environments. In some cases atkinson engines as well.

 

And even then, if the manual recommends 87 octane, the highest I'd be willing to go is 91. I wouldn't pay for 93.

Edited October 9, 2022 by MeeLee