Hybrids and 91 Octane Gas?

[hytibilly]

I just got a used 2019 Ford Fusion Hybrid. The manual says that 87 octane is sufficient but 91 octane would give better performance. What the heck is going on?

 

[AutoMechanic]

I didn’t know they still made cars that could run on 87 lol I heard that stopped long ago. I don’t run 87 in any of my vehicles.

 

[Skippy722]

Higher octane allows for more ignition advance and higher compression and/or boost, improving power and fuel economy.

 

[ecotourist]

I just got a used 2019 Ford Fusion Hybrid. The manual says that 87 octane is sufficient but 91 octane would give better performance. What the heck is going on?

My Accord says 87 octane is good enough too. But (so I'm told) the engine will perform better with 91 octane. I haven't tried it.

The performance with 87 is just fine. But I think what happens is that the spark will advance and provide even better performance with 91 octane.

 

[wpod]

What is going on?

 

[NH73]

Your engine computer control can adjust to what gas you are using.

 

[NH73]

I didn’t know they still made cars that could run on 87 lol I heard that stopped long ago. I don’t run 87 in any of my vehicles.

Yes, they still do. And a lot of then are designed that way. My 2017 RAV4 says not to use less than 87 octane.

 

[AutoMechanic]

Yes, they still do. And a lot of then are designed that way. My 2017 RAV4 says to use 87 octane.

Nice when my mom purchased her 2017 Camry they said only use mid-grade or higher to prevent the knock sensor from having to constantly turn on and wear out

 

[earlyre]

my 13 c-max hybrid just calls for 87....the only advantage i got was when the local casey's had E0 91. I got about 4-5 extra MPG's with that.
when they stopped carrying the E0 91, i tried E10 93 ( basically all the fuel here is E10)... I could tell no difference between it and 87.

these engines are N/A, Atkinson Cycle. no Boost...
I know there have been changes to the engines in the interval...
and i know the Ecoboost engines say that.. sure youre looking at the pages for the hybrid, and not not an ecoboost model?

-Edit-

huh... I'll be gosh darned...just downloaded the owners manual for both the hybrid and non hybrid fusions... same fuel text.. literally...

" Your vehicle is designed to operate on regular unleaded gasoline with a minimum pump (R+M)/2 octane rating of 87.
Some fuel stations, particularly those in high altitude areas, offer fuels posted as regular unleaded gasoline with an octane rating below 87. The use of these fuels could result in engine damage that will not be covered by the vehicle warranty.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.
Do not be concerned if the engine sometimes knocks lightly. However, if the engine knocks heavily while using fuel with the recommended octane rating, contact an authorized dealer to prevent any engine damage.
We recommend Top Tier detergent gasolines, where available to help minimize engine deposits and maintain optimal vehicle and engine performance. For additional information, refer to www.toptiergas.com.
Note:Use of any fuel for which the vehicle was not designed can impair the emission control system, cause loss of vehicleperformance, and cause damage to theengine which may not be covered by the vehicle Warranty.
Do not use:
•Diesel fuel.
•Fuels containing kerosene or paraffin.
•Fuel containing more than 15% ethanol or E85 fuel
•Fuels containing methanol.
•Fuels containing metallic-based additives, including manganese-based compounds.
•Fuels containing the octane booster additive, methylcyclopentadienyl manganese tricarbonyl (MMT).
•Leaded fuel, using leaded fuel is prohibited by law. "

 

[simple_gifts]

91 octane is 70 cents / gal more expensive here; Is it .7 dollars more performance? Unlikely.

Nice when my mom purchased her 2017 Camry they said only use mid-grade or higher to prevent the knock sensor from having to constantly turn on and wear out

Who is "they?"

 

[AutoMechanic]

91 octane is 70 cents / gal more expensive here; Is it .7 dollars more performance? Unlikely.

Who is "they?"

I feel it is. And they is the salesman at the dealership.

 

[4wd]

We have a 2014 Fusion Hybrid … 130k and counting on regular ️

 

[skyactiv]

You guys know the auto makers are trying to kill off 87 octane, don't you?
They cant market the more efficient gasoline engine designs they have in skunk works because Joe Dumb
will attempt to put 87 octane in his 2023 F150 and ruin the $13K engine.

 

[4wd]

You guys know the auto makers are trying to kill off 87 octane, don't you?
They cant market the more efficient gasoline engine designs they have in skunk works because Joe Dumb
will attempt to put 87 octane in his 2023 F150 and ruin the $13K engine.

It might

https://www.caranddriver.com/ford/f-150-electric

 

[kschachn]

Nice when my mom purchased her 2017 Camry they said only use mid-grade or higher to prevent the knock sensor from having to constantly turn on and wear out

The knock sensor is always turned on, and it will wear out at the same rate regardless of what is happening. I thought you were a mechanic?

 

[kschachn]

You guys know the auto makers are trying to kill off 87 octane, don't you?
They cant market the more efficient gasoline engine designs they have in skunk works because Joe Dumb
will attempt to put 87 octane in his 2023 F150 and ruin the $13K engine.

Raising the compression ratio and utilizing a higher octane gasoline is a legitimate way to improve efficiency. It’s also a lot cheaper and more reliable than the goofy things they’re doing now to try and eek out the last bit of improvement.

 

[kschachn]

Your engine computer control can adjust to what gas you are using.

Maybe. Maybe not.

 

[AutoMechanic]

The knock sensor is always turned on, and it will wear out at the same rate regardless of what is happening. I thought you were a mechanic?

I am, we always learned it would only kick on if the wrong gas was used to prevent pinging and knocking.

 

[kschachn]

I am, we always learned it would only kick on if the wrong gas was used to prevent pinging and knocking.

How would it know when to “kick on” if it was turned off? It is after all, the knock sensor. If the knock sensor isn’t sensing, how would it know when it’s knocking?

 

[NH73]

I feel it is. And they is the salesman at the dealership.

Things an auto salesman is good for: 1. Test drive a vehicle. 2. Sell a vehicle to you.
Otherwise, anything you want to know about a vehicle should be researched yourself online or in print. Far too often do salesman give wrong information or answer question incorrectly. You can even see owner's manuals online.