Found an Ethanol Limit Tuned on "E50"

[swamp2]

As some of you saw in my prior post about saving some $$ and gaining performance via ethanol (EtOH) I've been experimenting with various gas octanes and multiple ZFG tunes (91, 93 and E50). Also extensively using my fuel blending app which can blend to a desired octane level, big just EtOH %.

Unfortunately, I found a bit of a corner case for 87 base fuel at E60 (technically my EtOH meter said E59). My mix was to get to 97 octane. It's normally 98 octane at E50.

ZFG, as most tuners do, still call out a permissible EtOH for their E50 tune of 40-60%. As I've discussed elsewhere, octane is what really matters for a tune (as well as not using too so much EtOH that the fuel system can't keep up).

Anyway, when heading up into the mountains on a fast freeway section, it was hot, I was at about 4500' elevation, going uphill and it was windy. The fuel consumption was terrible and the turbos were working fairly hard. I was very likely about to go lean so the PCM kicked in, shut down the turbos and probably adjusted timing reducing power. I simply had too much EtOH for the fuel system at these conditions. I had the wrench icon and engine icon (IIRC). Restarting corrected things but the issue came right back. Luckily, there was a gas station nearby and I used my App to down blend to E50. I don't recall the resulting octane.

All the issues resolved and I was able to enjoy a great day of wheeling at Valley of the Moon here near San Diego.

It's worth noting that even under some prior hard pulls at E60 at sea level, on roads there was never a hint of problems. So again, it's a bit of a "corner case".

I don't really want to run different blends around town or in the mountains so I'll probably just stick with E50 and 98 octane for my E50 tune.

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[Bigmoose]

Do you know if the flow limits are the injectors or pump? I know other DI platforms have had success just upgrading the low pressure pump resulting in squeezing more volume from the high pressure pump.

 

[swamp2]

Do you know if the flow limits are the injectors or pump? I know other DI platforms have had success just upgrading the low pressure pump resulting in squeezing more volume from the high pressure pump.

Good question.

I couldn't tell from just the FORScan DTCs, I couldn't even definitively conclude lean or near lean. Obviously, with the HP Tuners suite (provided by ZFG with tunes) you can log everything of interest, but you've got to decide to log before any such event of interest.

 

[Spooled]

Do you know if the flow limits are the injectors or pump? I know other DI platforms have had success just upgrading the low pressure pump resulting in squeezing more volume from the high pressure pump.

the 3.0 needs a HPFP upgrade. Low-side has overhead. When I was helping ZFG develop the tuning we were hitting 90%+ duty cycle on E50 IIRC (Keep in mind, my tune is basically max effort as we were trying to find the limits)

Unfortunately HPFP upgrades are pricey. Too rich for my blood currently. To be able to run full E85 with upgraded turbos, you need about $5k worth of fuel system. An unfortunate downside for the platform being direct injection only

 

[Bigmoose]

the 3.0 needs a HPFP upgrade. Low-side has overhead. When I was helping ZFG develop the tuning we were hitting 90%+ duty cycle on E50 IIRC (Keep in mind, my tune is basically max effort as we were trying to find the limits)

Unfortunately HPFP upgrades are pricey. Too rich for my blood currently. To be able to run full E85 with upgraded turbos, you need about $5k worth of fuel system. An unfortunate downside for the platform being direct injection only

Good info. Do you know if the low pressure pump pressure can be raised? I think the newer systems are essentially return fuel systems with the regulator in the fuel hat instead of at the engine.

 

[GooseTuned]

As some of you saw in my prior post about saving some $$ and gaining performance via ethanol (EtOH) I've been experimenting with various gas octanes and multiple ZFG tunes (91, 93 and E50). Also extensively using my fuel blending app which can blend to a desired octane level, big just EtOH %.

Unfortunately, I found a bit of a corner case for 87 base fuel at E60 (technically my EtOH meter said E59). My mix was to get to 97 octane. It's normally 98 octane at E50.

ZFG, as most tuners do, still call out a permissible EtOH for their E50 tune of 40-60%. As I've discussed elsewhere, octane is what really matters for a tune (as well as not using too so much EtOH that the fuel system can't keep up).

Anyway, when heading up into the mountains on a fast freeway section, it was hot, I was at about 4500' elevation, going uphill and it was windy. The fuel consumption was terrible and the turbos were working fairly hard. I was very likely about to go lean so the PCM kicked in, shut down the turbos and probably adjusted timing reducing power. I simply had too much EtOH for the fuel system at these conditions. I had the wrench icon and engine icon (IIRC). Restarting corrected things but the issue came right back. Luckily, there was a gas station nearby and I used my App to down blend to E50. I don't recall the resulting octane.

All the issues resolved and I was able to enjoy a great day of wheeling at Valley of the Moon here near San Diego.

It's worth noting that even under some prior hard pulls at E60 at sea level, on roads there was never a hint of problems. So again, it's a bit of a "corner case".

I don't really want to run different blends around town or in the mountains so I'll probably just stick with E50 and 98 octane for my E50 tune.

Do you know what specific DTC's you got?

Reason I ask is because likely what happened to you has nothing to do with ethanol content/fueling at all.

 

[GooseTuned]

Good info. Do you know if the low pressure pump pressure can be raised? I think the newer systems are essentially return fuel systems with the regulator in the fuel hat instead of at the engine.

You can raise pressure, it's only going to hurt performance though.

Raising pressure doesn't do much, volume is what you want in this case. The upgraded big bore pump actually lowers pressure because it flows more volume.

If you look at fuel pressure vs engine RPM, you can see the pump efficiency is best at 2175psi, with a max pressure set in the tune at 3600psi. Running a higher pressure pump efficiency goes down quite a bit. Also adds more heat as well.

View attachment 792483

 

[swamp2]

Do you know what specific DTC's you got?

Reason I ask is because likely what happened to you has nothing to do with ethanol content/fueling at all.

There wasn't a lot.

P0299 - Turbocharger/Supercharger Underboost

And a PCM "Freeze Frame"

A year ago, before tuned and before running EtOH, I also had a turbo shut down, same P0299 and it was due to a loose wastegate locknut. A known Bronco issue. TSB (and my story) here.

Thanks in advance!

 

[Bigmoose]

You can raise pressure, it's only going to hurt performance though.

Raising pressure doesn't do much, volume is what you want in this case. The upgraded big bore pump actually lowers pressure because it flows more volume.

If you look at fuel pressure vs engine RPM, you can see the pump efficiency is best at 2175psi, with a max pressure set in the tune at 3600psi. Running a higher pressure pump efficiency goes down quite a bit. Also adds more heat as well.

View attachment 792483

I was referring to the low pressure pump in the tank which I don’t believe you can control via ecu, unless its like returnless systems of old that use a variable pump driver.

I was curious if you increased the low pressure inlet to the high pressure pump if that would bump up the efficiency and flow. I know other platforms do this to get extra headroom from the high pressure pump so they can run more ethanol without replacing the expense hpp.

 

[GooseTuned]

There wasn't a lot.

P0299 - Turbocharger/Supercharger Underboost

And a PCM "Freeze Frame"

A year ago, before tuned and before running EtOH, I also had a turbo shut down, same P0299 and it was due to a loose wastegate locknut. A known Bronco issue. TSB (and my story) here.

Thanks in advance!

Gotcha, yeah this is not related to ethanol content. Too high of ethanol content would be a set of different codes.

 

[GooseTuned]

I was referring to the low pressure pump in the tank which I don’t believe you can control via ecu, unless its like returnless systems of old that use a variable pump driver.

I was curious if you increased the low pressure inlet to the high pressure pump if that would bump up the efficiency and flow. I know other platforms do this to get extra headroom from the high pressure pump so they can run more ethanol without replacing the expense hpp.

Ah ok. Ya you can control it. It's just a lift pump though, and that has, up to this point, not been an issue making power since the high side does the heavy lifting.

I bump this exact pressure on the dual injected raptors (3.5L raptors) and it helps, but this system doesn't really benefit from it the same way.

 

[swamp2]

Gotcha, yeah this is not related to ethanol content. Too high of ethanol content would be a set of different codes.

Well, lowering to 50% EtOH immediately and completely fixed the issue for over a week.

After said week, I did check with my service dealer as to the known issue of wastegate actuator arm nut retorquing as they did the passenger side only (which threw the same code on pump gas 1 year or so ago). I did the drivers side as an extra precaution.

Have driven the wheels off her since on only FP tune and zero recurrence.

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