2014 F150 Ecoboost, 5W30 Pennzoil UP - Opinions?

[philosopheriam]

Originally Posted By: badtlc
premium will likely eliminate your fuel dilution. run premium (91+ octane) for an entire OCI and sample again if you want to test for yourself.


How exactly would premium fuel eliminate the fuel dilution issue, which is caused by three main factors:

High fuel pressures inherent to the design of a DI fuel system
Increased cylinder pressures due to turbocharging
A PCV system that could have used more thought from the Ford engineers

 

[bigt61]

I would have left the FF oil in until the OLM said to change it. An early switch to synthetic delays ring seating IMO. Try a few 5k runs w semi-synthetic and then do another UOA. I'll bet the fuel dilution issue will improve. Thanks for posting the UOA.

 

[Greasymechtech]

Stick with premium fuel. ECU will overreact when knock sensor nags it, usually leading to timing cut and pig rich fuel,... which leads to more dilution.

The 0w40's will give you the extra point or 2 of viscosity to help offset dilution. Thick Euro 5w30s, 0w30s'... are another option.

GM reprogrammed their DI oil life monitors because of fuel dilution caused failures, just about cutting the mileage oil change interval in half. Hyundai GDI's recently got hit with a class action. DI seems to be an issue across the board...from carbon buildup, fuel dilution, failures... with multiple makes.

If you stick with 5w30, I would not go past 5k, especially if regular or midgrade fuel is a habit.

Copper... just break in wear.
Silicon... gasket material.
Both will drop with future intervals.

 

[badtlc]

Originally Posted By: philosopheriam
Originally Posted By: badtlc
premium will likely eliminate your fuel dilution. run premium (91+ octane) for an entire OCI and sample again if you want to test for yourself.


How exactly would premium fuel eliminate the fuel dilution issue, which is caused by three main factors:

High fuel pressures inherent to the design of a DI fuel system
Increased cylinder pressures due to turbocharging
A PCV system that could have used more thought from the Ford engineers


Due to the high combustion chamber pressures, DI engines control knock through A:F ratios in addition to timing. When running 87 octane, the ECU tunes very rich. The excessive fuel vapor cools the combustion chamber to prevent knocking. When you run a higher octane, the ECU allows the A:F to lean out.

This has shown to be true for the Mazda DI engines (backed up by UOAs on this forum) and from what I have been able to read, almost all DI engines with high compression have the same capabilities.

 

[SteveSRT8]

Originally Posted By: badtlc
Originally Posted By: philosopheriam
Originally Posted By: badtlc
premium will likely eliminate your fuel dilution. run premium (91+ octane) for an entire OCI and sample again if you want to test for yourself.


How exactly would premium fuel eliminate the fuel dilution issue, which is caused by three main factors:

High fuel pressures inherent to the design of a DI fuel system
Increased cylinder pressures due to turbocharging
A PCV system that could have used more thought from the Ford engineers


Due to the high combustion chamber pressures, DI engines control knock through A:F ratios in addition to timing. When running 87 octane, the ECU tunes very rich. The excessive fuel vapor cools the combustion chamber to prevent knocking. When you run a higher octane, the ECU allows the A:F to lean out.

This has shown to be true for the Mazda DI engines (backed up by UOAs on this forum) and from what I have been able to read, almost all DI engines with high compression have the same capabilities.


And so do many others. Most any engine these days has the ability to vary mixture and timing significantly to reduce knock. Hypereutectic pistons with very high top rings are a real reason knock must be carefully controlled, with of course emissions being primary.

Fuel dilution is very common in high performance N/A engines like my sig car and Overkill's BMW M5. Fuel is used as a coolant, literally...

 

[philosopheriam]

Originally Posted By: badtlc
Originally Posted By: philosopheriam
Originally Posted By: badtlc
premium will likely eliminate your fuel dilution. run premium (91+ octane) for an entire OCI and sample again if you want to test for yourself.


How exactly would premium fuel eliminate the fuel dilution issue, which is caused by three main factors:

High fuel pressures inherent to the design of a DI fuel system
Increased cylinder pressures due to turbocharging
A PCV system that could have used more thought from the Ford engineers


Due to the high combustion chamber pressures, DI engines control knock through A:F ratios in addition to timing. When running 87 octane, the ECU tunes very rich. The excessive fuel vapor cools the combustion chamber to prevent knocking. When you run a higher octane, the ECU allows the A:F to lean out.

This has shown to be true for the Mazda DI engines (backed up by UOAs on this forum) and from what I have been able to read, almost all DI engines with high compression have the same capabilities.


To my knowledge, there are numerous Ecoboost owners running premium fuel and fuel dilution is still a major issue - if I am incorrect I will eat a piece of crow pie immediately

Even running premium, I can only speculate that the ECU will only be able to lean the mixture so much - this is a turbocharged engine and lean AFR's will cause cylinder temperatures to increase dramatically.

Also, here's a bit of math:

Let's assume we have a truck with 100000mi - over this mileage span, the fuel cost would be the following (in my neck of the woods, premium is usually anywhere from 30 to 40 cents more per gallon. Let's assume that it averages to be 35 cents more per gallon:

100000mi/17mpg * $2.64gal = $15529 total fuel cost
100000mi/17mpg * $2.99gal = $17588 total fuel cost
TOTAL DIFFERENCE = $2059 more to run premium

100000mi/5000mi OCI * $33 per oil change = $660 in oil changes
100000mi/3000mi OCI * $33 per oil change = $1100 in oil changes
TOTAL DIFFERENCE FROM 5000mi to 3000mi OCI's = $440

You can change a lot of oil for $2059!

 

[badtlc]

Originally Posted By: philosopheriam
Originally Posted By: badtlc
Originally Posted By: philosopheriam
Originally Posted By: badtlc
premium will likely eliminate your fuel dilution. run premium (91+ octane) for an entire OCI and sample again if you want to test for yourself.


How exactly would premium fuel eliminate the fuel dilution issue, which is caused by three main factors:

High fuel pressures inherent to the design of a DI fuel system
Increased cylinder pressures due to turbocharging
A PCV system that could have used more thought from the Ford engineers


Due to the high combustion chamber pressures, DI engines control knock through A:F ratios in addition to timing. When running 87 octane, the ECU tunes very rich. The excessive fuel vapor cools the combustion chamber to prevent knocking. When you run a higher octane, the ECU allows the A:F to lean out.

This has shown to be true for the Mazda DI engines (backed up by UOAs on this forum) and from what I have been able to read, almost all DI engines with high compression have the same capabilities.


To my knowledge, there are numerous Ecoboost owners running premium fuel and fuel dilution is still a major issue - if I am incorrect I will eat a piece of crow pie immediately

Even running premium, I can only speculate that the ECU will only be able to lean the mixture so much - this is a turbocharged engine and lean AFR's will cause cylinder temperatures to increase dramatically.

Also, here's a bit of math:

Let's assume we have a truck with 100000mi - over this mileage span, the fuel cost would be the following (in my neck of the woods, premium is usually anywhere from 30 to 40 cents more per gallon. Let's assume that it averages to be 35 cents more per gallon:

100000mi/17mpg * $2.64gal = $15529 total fuel cost
100000mi/17mpg * $2.99gal = $17588 total fuel cost
TOTAL DIFFERENCE = $2059 more to run premium

100000mi/5000mi OCI * $33 per oil change = $660 in oil changes
100000mi/3000mi OCI * $33 per oil change = $1100 in oil changes
TOTAL DIFFERENCE FROM 5000mi to 3000mi OCI's = $440

You can change a lot of oil for $2059!


You can debate it all you want but the proof is in the pudding (UOAs). It does make a difference.

 

[philosopheriam]

"You can debate it all you want but the proof is in the pudding (UOAs). It does make a difference"

I'm not trying to be argumentative for the sake of being argumentative - my fundamental question is this - if you run 87 octane and see 5+ % fuel dilution over 5000mi, and if you then run premium and see 5+ % fuel dilution over 5000mi, then what's the difference? I haven't seen any UOA's where premium fuel *greatly* impacted fuel dilution numbers. If there are some UOA's out there contrary to my belief, I really want to see them so the benefit can be measured and not just anecdotal...