First fill up - Premium fuel?

[aplusgeek]

Hello everyone,

 

I've read a few topics here and most people seem to be recommending regular gasoline for the fusion. However, in my manual it states that premium (91 octane) is preferred to get max mpg and performance?

 

What does everyone here recommend?

 

I drive 2017 Ford Fusion Energi

 

Thanks

[murphy]

Hello everyone,

 

I've read a few topics here and most people seem to be recommending regular gasoline for the fusion. However, in my manual it states that premium (91 octane) is preferred to get max mpg and performance?

 

What does everyone here recommend?

 

I drive 2017 Ford Fusion Energi

 

Thanks

Are you sure that you aren't looking at the manual for the standard Fusion?

 

The manual title includes Hybrid / Energi for the Hybrid and the Energi.

 

From my manual

 

Octane Recommendations

Regular unleaded gasoline with a pump

(R+M)/2 octane rating of 87 is

recommended. Some fuel stations offer

fuels posted as regular with an octane

rating below 87, particularly in high altitude

areas. Fuels with octane levels below 87

are not recommended.

Do not be concerned if your engine

sometimes knocks lightly. However, if it

knocks heavily while you are using fuel with

the recommended octane rating, see your

authorized dealer to prevent any engine

damage.

 

My Energi works fine on regular (87 octane).

That is when the engine starts.  It usually doesn't start from late spring through early fall.

[Russael]

I am rescinding this remark.  It was inaccurate.

 

The 2.0L turbo Fusion can take advantage of higher octane ratings (It will advance timing slightly to give more HP).  On regular 87, the 2L turbo does 232 HP.  On 93, it'll do 240.

Edited May 22, 2017 at 11:56 PM by Russael

[aplusgeek]

Are you sure that you aren't looking at the manual for the standard Fusion?

 

The manual title includes Hybrid / Energi for the Hybrid and the Energi.

 

From my manual

 

Octane Recommendations

Regular unleaded gasoline with a pump

(R+M)/2 octane rating of 87 is

recommended. Some fuel stations offer

fuels posted as regular with an octane

rating below 87, particularly in high altitude

areas. Fuels with octane levels below 87

are not recommended.

Do not be concerned if your engine

sometimes knocks lightly. However, if it

knocks heavily while you are using fuel with

the recommended octane rating, see your

authorized dealer to prevent any engine

damage.

 

My Energi works fine on regular (87 octane).

That is when the engine starts.  It usually doesn't start from late spring through early fall.

 

You're right I think I may have looked at the regular fusion manual that was included.

 

What do you mean when the engine starts? Are you having engine issues?

[murphy]

You're right I think I may have looked at the regular fusion manual that was included.

 

What do you mean when the engine starts? Are you having engine issues?

No.  I don't use the engine if I can avoid it.  The vast majority of my driving is in EV Now mode.  I put gas in my gas tank about once a year.

[aplusgeek]

No.  I don't use the engine if I can avoid it.  The vast majority of my driving is in EV Now mode.  I put gas in my gas tank about once a year.

Oh that's pretty good. Yeah I can't get away with that, I put about 150km on mine daily.

[bdginmo]

As others have pointed out the Atkinson cycle engines in the Fusion Hybrid/Energi cannot take advantage of higher octane fuels. So there is no benefit in using an octane higher than 87.

 

For the EcoBoost engines the torque and horsepower ratings are actually achieved with 93 octane fuel. The computer for those engines uses what is called an octane adjustment ratio to tune the valve timing, spark timing, and various other parameters to achieve better performance with higher octane fuel. The OAR is derived by the constantly trying to tweak parameters slightly to learn what the optimal values should be. A quick learn apparently happens on just a few full throttle accelerations, but a more complete learn can take up to a full tank of gas.

[Tjien]

For 2017 Ford Fusion Energi, here is the quote from owner's manual page 154. 

 

"For best overall vehicle and engine performance, premium fuel with an octane rating of 91 or higher is recommended."

 

Octane rating 87 is the MINIMUM requirement. 

 

For the first fill up, I used Octane 87 fuel, and I felt my car was not as smooth and responsive as the tester car, and the tester car only has 25 km (both cars were 2017 Ford Fusion Titanium trim). On the second fill up, I used Octane 93, and the gas engine was running smoother and more responsive.

 

I will stick with Octane 93, since I only fill up the tank once every 2-3 month. Using 87 octane rating won't harm the car, you have a choice.

[Timewellspent]

When I look at page 154 of the 2017 Energi manual I see the following.  Note this is from first printing. 

 

[Tjien]

I got the pdf version online, here -> http://www.fordservicecontent.com/Ford_Content/Catalog/owner_information/2017-Fusion-Hybrid-Owner-Manual-version-3_OM_EN-US_02_2017.pdf

 

you can also check the html version here -> http://www.fordservicecontent.com/Ford_Content/vdirsnet/OwnerManual/Home/Index?bookcode=O34127&marketCode=US&languageCode=EN&VIN=&div=f

 

The latest pdf version is version 3, I have all 3 versions, Starting in version 2, the fuel recommendation is Octane 91 or higher.

 

I think they made the revision in version 2. The very latest version is always in the html version.

[Russael]

Interesting.. you're right - it does say below the minimum recommendation that it recommends 91 octane for 2017 models.  I checked my 2013 manual and even though there is a 3rd printing of that, it says 87 is the recommended one with no mention of anything better.  Funny that it also says the motor may knock slightly.  It makes me wonder if using a better fuel in the summer would improve economy or not.

[bdginmo]

That is interesting. I wonder if the newer models have control logic that dynamically tunes engine performance based on fuel characteristics like the EB engines.

[jaydubau]

Interesting.. you're right - it does say below the minimum recommendation that it recommends 91 octane for 2017 models.  I checked my 2013 manual and even though there is a 3rd printing of that, it says 87 is the recommended one with no mention of anything better.  Funny that it also says the motor may knock slightly.  It makes me wonder if using a better fuel in the summer would improve economy or not.

 

From the manual...."For best overall vehicle and engine performance, premium fuel with an octane rating of 91 or higher is recommended. The performance gained by using premium fuel is most noticeable in hot weather...."

 

So, apparently, you can get away with using 87 octane rating, but there are advantages to moving up to 91 or higher octane rating. I wonder if there's a knock sensor or something similar that, for example, keeps a more advanced ignition timing setting for better performance that would create knock using 87, but doesn't using 91.

 

Is that what it boils down to?

[bdginmo]

From the manual...."For best overall vehicle and engine performance, premium fuel with an octane rating of 91 or higher is recommended. The performance gained by using premium fuel is most noticeable in hot weather...."

 

So, apparently, you can get away with using 87 octane rating, but there are advantages to moving up to 91 or higher octane rating. I wonder if there's a knock sensor or something similar that, for example, keeps a more advanced ignition timing setting for better performance that would create knock using 87, but doesn't using 91.

 

Is that what it boils down to?

 

Yes probably. It sounds like it might be a more limited type of timing adjustment than what the EcoBoost engines do. One thing to watch out for with premium gas is that a lot of stations sell it E0 (no ethanol) as opposed to E10. This can give you the mistaken impression that it was the higher octane that improved MPG when in reality it was because it was pure gasoline instead of an gas-ethanol blend.

[aplusgeek]

So just an update and fyi. Towards the end of the fuel that came from the dealer I would hear a sporadic engine knock. When I consequently filled up with premium the smoothness returned and it's been smooth sailing since.

 

So the dealer probably filled up 87 octane.

 

At 91 octane the car runs smoothly and quietly, I am putting on approximately 1000km a week right now. And I love being able to drive almost 1000km with a single tank :) , in my previous car (Jeep wrangler) that was 3 fill ups - i.e. $200

[jj2me]

FWIW, the following was on an old November 27th, 2016 Motorweek TV broadcast. It's from a question and answer session between Pat Goss of Motorweek and Brian West of Oak Ridge National Laboratory about use of premium fuel:

 

Goss: "Other common questions [...] more cleaning agents?"

 

West: "In some cases, that may be true.  In fact, some manufacturers recommend premium because the fuel can sit in the tank a long time, say in the case of a plug-in hybrid."

Edited August 9, 2017 at 05:02 PM by jj2me

[murphy]

The Energi has a pressurized fuel system.  Fuel doesn't go bad like it would in a regular unpressurized fuel system.  The Energi monitors the use and addition of fuel.  If fuel has been in the tank, without any additions, for 18 months the car enters a mode that forces the use of fuel only until the tank is down to about 1/8.  I last put fuel in mine on April 8, and that was just $5.00 worth.