Minimum octane for 2016 2.0 ecoboost?

[ARCOgraphite]

Originally Posted by LoneRanger
My new F150 with the 2.7 ecoboost recently ran worse on a tank mid grade 89 than it has been 87. Just filled up with 18 gal of 87 (23 gal tank) and it's back to normal again. Owner manual says 87 is okay.

Over on F150forum.com there was a recent poll and 58% of respondents reported using 87 in their ecoboost. 323 respondents total, 188 said 87. 13 said midgrade (89), premium (91 & 93) was 122.


Yeah, same here. I don't know what's going on with the higher octane fuels.

Not consistently good.

 

[Garak]

There may be a benefit. Whether it's worth the premium price, only you can answer. You'll never get a fuel economy boost enough to make up the difference. However, that's not the only consideration.

 

[TiredTrucker]

I notice a definite improvement in performance using 100 octane E85 in the wife's 2.4L Equinox compared to non ethanol. As for whether it delivers better MPG, no, actually less MPG, but still the actual cost per mile is cheaper using the E85. Currently, E85 is $1.89 in my area. Premium is $3.01. The Nox gets an average of 24 MPG on E85. For equity, it would have to get over 38 MPG using premium. Will not happen except going downhill with a tail wind. So for us, E85 is very cost effective to use and the result is better performance.

 

[4x4le]

The biggest thing is if it has direct injection or not. If it just has multi-port injection, 87 is a bad idea on turbo motors period. Knock sensors require knock to happen before switching to knock maps in the ecu or for timing to be pulled and fuel added (which then just kills the money you saved at the pump). Also the very first time your engine knocks you could crack a piston, its perhaps not the most likely thing to happen but knock is the equivalent of someone bringing a hammer down on your piston as it is coming up. It can distort your bearings and crack pistons, bend rods and break cranks.

I has an 11 cruze eco and the manual said 87 was ok and 91+ was recommended. People were running 87 exclusively and getting warranty claims for broken ringlands denied because fuel quality is not covered. Gm was saying good 87 would not have done that.........

So find out if it is di or port.

 

[TiredTrucker]

There have been many problems associated with using low octane fuels with high compression GDI engines, especially the turbo varieties. LSPI has become enough of a problem that it even led to upgrades in oil specifications in an attempt to reduce the problem And the OEM's have really gone all in regarding down speeding of engines for fuel economy, to wit, the move to taller and taller final gear ratios. Combine that engine down speeding with low octane fuel and high compression and one has a high probability of LSPI (low speed pre ignition). The ECM would try to compensate by changing timing and injection, but that is degrading the performance. While maybe within the design parameters, it is not the best for the engine and in many cases abuse of the engine.

One is going to have to realize that the only way to mitigate such issues is to use a higher octane fuel on a regular basis. The price to pay for the OEM's making engines smaller and smaller while trying to get them to output the power of a big block muscle car engine. One is going to separate more of their money from their wallet by using premium grade fuel, but it is also a high probability that if they use regular fuel in these high compression engines, it will end up costing them even more than if they had just bit the bullet and got the higher octane fuel all along A OEM may say using regular is fine, as they are trying to market vehicles and sell them. Harder to sell vehicles that require the highest cost fuel available. But if they can tell the consumer that regular is ok and get thru the warranty period, they have no worries. But the consumer ends up getting hosed in the end. Any owner with one of these engines needs to take a long look at what they are doing, get a little up to speed on the realities, and use some sense. One can bury their head in a bucket and ignore these realties, or they can be proactive in protecting their investment in a vehicle.

 

[tdi jerry]

Originally Posted by Miller88
They will get better fuel mileage running higher octane fuel. In some cases enough more fuel mileage to pay for premium, in other cases not.

My two ford fusions also get better gas mileage with higher octane fuels. On average i get two to three miles more with higher octane fuel on my 18 mile commute to work.

 

[4x4le]

Originally Posted by tdi jerry
Originally Posted by Miller88
They will get better fuel mileage running higher octane fuel. In some cases enough more fuel mileage to pay for premium, in other cases not.

My two ford fusions also get better gas mileage with higher octane fuels. On average i get two to three miles more with higher octane fuel on my 18 mile commute to work.

If higher octane gets you better fuel economy then you are knocking on 87 and the knock sensor is hopefully catching it and switching you to knock maps. Everytime your car starts it will be on the standard fuel/timing maps and wait to knock again. It is a smart choice where you just run premium. Every instance of knock is capable of damaging your engine.

 

[Snagglefoot]

.[/quote] From 4x4le
If higher octane gets you better fuel economy then you are knocking on 87 and the knock sensor is hopefully catching it and switching you to knock maps. Everytime your car starts it will be on the standard fuel/timing maps and wait to knock again. It is a smart choice where you just run premium. Every instance of knock is capable of damaging your engine. [/quote]

Interesting thought but I don't believe this is true. On vehicles with knock sensors, the computer is constantly adjusting the timing and senses the onset of knocking way before it's capable of damaging the engine.

 

[4x4le]

If oem knock sensors were that good then professional tuners would not spend 300-400 times as much money on equipment in order to be able to detect knock. Oem knock sensors (even today) are a joke and it takes very little to to cause then to read wrong.

Also I have never saw an ecu do open loop knock combatting. The epa would be very quick to consider that a "defeat device" and wouldn't have a good basis for emissions testing the vehicles if the timing were allowed to be pulled at will based on a cheap knock sensor.
In reality you have a fuel and timing map, and a knock fuel and timing map. In most cases a certain threshold of knock must occur and then the fuel and timing maps will switch. In some cases (some ecus) may switch just the timing or just the fuel map to see if the knock threshold has lowered enough without having to switch both maps. Either way every combination of fuel and timing maps must be emissions certified or cause a check engine light if not.
Cylinder pressure sensors would be the only way to activle detect knock on a ecu before any possibility of causing damage. Everything else is just wishful thinking on the parts of those who want to save at the pump and oems betting that it will make it past 60k miles.

 

[Skippy722]

Originally Posted by Snagglefoot

Interesting thought but I don't believe this is true. On vehicles with knock sensors, the computer is constantly adjusting the timing and senses the onset of knocking way before it's capable of damaging the engine.


That's exactly what I've seen... ST KR, and LT KR. You'll have some ST KR, which is sometimes just "noise" depending on how sensitive the sensors are, but you don't want any long term.

 

[Dave9]

Originally Posted by 4x4le
If oem knock sensors were that good then professional tuners would not spend 300-400 times as much money on equipment in order to be able to detect knock.


OEM knock sensors are set up for the stock engine, which they spend millions to test, far more than some pro tuner does, and have millions of vehicles racking up billions of miles. For this latter reason, I wouldn't have trusted the first couple years of Ecoboost engines but now we have historical data and knock damage just isn't a widespread epidemic.

If it were a problem, the last thing they would do is list 87 octane in the owner's manual because it wouldn't take years (under warranty) for this problem to surface.

 

[4x4le]

Originally Posted by Dave9
Originally Posted by 4x4le
If oem knock sensors were that good then professional tuners would not spend 300-400 times as much money on equipment in order to be able to detect knock.


OEM knock sensors are set up for the stock engine, which they spend millions to test, far more than some pro tuner does, and have millions of vehicles racking up billions of miles. For this latter reason, I wouldn't have trusted the first couple years of Ecoboost engines but now we have historical data and knock damage just isn't a widespread epidemic.

If it were a problem, the last thing they would do is list 87 octane in the owner's manual because it wouldn't take years (under warranty) for this problem to surface.


My very first post in this thread I state that if the ecoboost is direct injection then 87 is ok, and if not then no. Nothing you have said changes my mind or any facts. So yes the ecoboost is direct injection and therefore not really subject to knock in the first place. A direct injection engine is not an engine you make the case FOR knock sensors being good with, knock sensors being (what they are) junk helped prompt gas direct injection engines in the first place.
You also imply how bad reliability can be after these engeneers spend billions testing engines and cars but in the same breath imply the oems can be trusted.



The oems (on most vehicles) only care about making it past warranty period and the consumers of newly released vehicles/engines pay a premium to be a beta tester for the oem.

 

[BeerCan]

I run 87 in all my Ecoboost vehicles . The only exception is the F-150 when I tow. Then it's 93

 

[DavidJones]

Ford's do not have a LSPI problem.

Originally Posted by TiredTrucker
There have been many problems associated with using low octane fuels with high compression GDI engines, especially the turbo varieties. LSPI has become enough of a problem that it even led to upgrades in oil specifications in an attempt to reduce the problem And the OEM's have really gone all in regarding down speeding of engines for fuel economy, to wit, the move to taller and taller final gear ratios. Combine that engine down speeding with low octane fuel and high compression and one has a high probability of LSPI (low speed pre ignition). The ECM would try to compensate by changing timing and injection, but that is degrading the performance. While maybe within the design parameters, it is not the best for the engine and in many cases abuse of the engine.

One is going to have to realize that the only way to mitigate such issues is to use a higher octane fuel on a regular basis. The price to pay for the OEM's making engines smaller and smaller while trying to get them to output the power of a big block muscle car engine. One is going to separate more of their money from their wallet by using premium grade fuel, but it is also a high probability that if they use regular fuel in these high compression engines, it will end up costing them even more than if they had just bit the bullet and got the higher octane fuel all along A OEM may say using regular is fine, as they are trying to market vehicles and sell them. Harder to sell vehicles that require the highest cost fuel available. But if they can tell the consumer that regular is ok and get thru the warranty period, they have no worries. But the consumer ends up getting hosed in the end. Any owner with one of these engines needs to take a long look at what they are doing, get a little up to speed on the realities, and use some sense. One can bury their head in a bucket and ignore these realties, or they can be proactive in protecting their investment in a vehicle.

 

[4x4le]

You will have to be more specific. I have been in many fords that knock at high load low rpm. New direct injection engines shouldn't though.