System too lean

[honeybadger]

As mentioned above, I am going to see if this is an e85 reaction. I know the profile itself isn't causing any issues since I had it on the car for two years prior to adding tb. It's understandable that I'm now getting more air than fuel, but is it within specs since it isn't throwing a dash cel?

Do you think bad e85 could cause this condition?

typically bad e85 will cause the ECU to richen up fueling, but again, that's when it's tuned for it. No idea how the proflex impacts since the closed-loop fueling is broken.

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[SheepDog]

you're not getting any performance benefits from E85 without a tune. The OEM ecu is not programmed to take advantage of it

I would argue that a slight power increase would be possible because there's no way that the engine is near MBT on shitty California 91 octane. The flex fuel thing must be adding some fuel/DC to the injectors, because otherwise he would be somewhere around 30% fuel trims

 

[robvas]

Actual dyno will say otherwise - you're not getting any performance benefits from E85 without a tune. The OEM ecu is not programmed to take advantage of it even if it knew it was running ethanol - which the proflex doesn't fix. You're not going to get more power without adjusting the the fueling and ignition tables. If there was power to be had with just fuel, Ford would've posted a 100 octane power figure. But 100 octane doesn't improve power without a tune, just reduces likelihood of pre-detonation

With the Proflex, will the car still add timing based on not seeing knock, just like if you were to add boostane?

I thought other people had posted increases in HP on the dyno with 350's using 98/100 octane fuel on the stock tune?

 

[honeybadger]

I would argue that a slight power increase would be possible because there's no way that the engine is near MBT on shitty California 91 octane. The flex fuel thing must be adding some fuel/DC to the injectors, because otherwise he would be somewhere around 30% fuel trims

While I agree with your hypothesis, I personally view this as semantics. The OEM ecu is always going to maximize engine performance based on knock/AFR regardless of what fuel is in it (within the set parameters that Ford setup in the ECU). The problem is that those parameters are not optimized for E85 - which allows for more timing and other changes.

The truth is we don't really have any idea how the proflex is changing what the ECU is doing without data logging a before and after. All we know is that it uses a multiplier on the injectors to compensate for the ethanol content.

 

[SheepDog]

While I agree with your hypothesis, I personally view this as semantics. The OEM ecu is always going to maximize engine performance based on knock/AFR regardless of what fuel is in it (within the set parameters that Ford setup in the ECU). The problem is that those parameters are not optimized for E85 - which allows for more timing and other changes.

The truth is we don't really have any idea how the proflex is changing what the ECU is doing without data logging a before and after. All we know is that it uses a multiplier on the injectors to compensate for the ethanol content.

The factory calibration can/will add timing with additional octane. Adding a few gallons of E85 to the tank (to an otherwise full tank of Gasoline), will produce more timing and power up to a point. (like you said, within the parameters that Ford set). E85 is well outside of those parameters and only increasing duty cycle on the injectors is not ideal.


The Proflex device seems like a gamble in regard to reliability and performance.

 

[saleen367]

It is my humble opinion that anytime you create a situation that increases or decreases airflow, fuel (E85), the stock ECU can only compensate so much so for the data it receives. So, if you want a safe (think AFR) and maximum performing engine, you need a tune, no question. While the Proflex might work within the parameters of its intended use, are you willing to bet your engine on it?

 

[526 HRSE]

There are plenty of dyno's online showing the increase in HP and torque from running the Proflex alone. Personally, it didn't feel like a whole lot prior to my other mods. I went this route due to warranty that i still have for another 3 years. Once i changed the throttle body is was like night and day with the torque. It's got to be a synergistic effect because i'm not sure a throttle body alone will do this.

I'm aware that i'm leaving HP on the table. Faster than it is now is going to be hell keeping the tires on the ground. As of now without traction control on now, forget about it.

The main questions are,

1) is the system running too lean, but not lean enough to throw a cel, and if so, what is the risk of running slightly lean over any period of time. Of course, my MPG is horrible.

2) outside of removing air, the only way to introduce more fuel is through a tune? (which i don't want to do due to warranty)

 

[526 HRSE]

It is my humble opinion that anytime you create a situation that increases or decreases airflow, fuel (E85), the stock ECU can only compensate so much so for the data it receives. So, if you want a safe (think AFR) and maximum performing engine, you need a tune, no question. While the Proflex might work within the parameters of its intended use, are you willing to bet your engine on it?

I've never heard of an engine failing because of a proflex, but i've read numerous stories on tuning nightmares.

 

[robvas]

Once i changed the throttle body is was like night and day with the torque. It's got to be a synergistic effect because i'm not sure a throttle body alone will do this.

Bigger TB opens faster, usually it's very noticeable. It's what people refer to as 'throttle response' and even though the peak HP might not be higher, the car feels faster

 

[526 HRSE]

Bigger TB opens faster, usually it's very noticeable. It's what people refer to as 'throttle response' and even though the peak HP might not be higher, the car feels faster

More fuel, more air, more fire, more HP. (on time) But, i'm running lean now.

It's got me thinking more about the fuel cleaner i just ran through. Maybe the ECU just hasn't figured things out yet. I never thought to check this prior because there were no issues, no dash light.

I'll run out the e85 tomorrow and run some 91 back through it. Maybe that Reno gas i put in it last week weirded my car out.

 

[robvas]

Do a a pull or two, log the AFR, STFT, LTFT, fuel pump duty, fuel pressure...

 

[junits15]

There are plenty of dyno's online showing the increase in HP and torque from running the Proflex alone. Personally, it didn't feel like a whole lot prior to my other mods. I went this route due to warranty that i still have for another 3 years. Once i changed the throttle body is was like night and day with the torque. It's got to be a synergistic effect because i'm not sure a throttle body alone will do this.

I'm aware that i'm leaving HP on the table. Faster than it is now is going to be hell keeping the tires on the ground. As of now without traction control on now, forget about it.

The main questions are,

1) is the system running too lean, but not lean enough to throw a cel, and if so, what is the risk of running slightly lean over any period of time. Of course, my MPG is horrible.

2) outside of removing air, the only way to introduce more fuel is through a tune? (which i don't want to do due to warranty)

I think i can explain why I think its the proflex and it will help you debug.
The system targets a lambda, value The ECU is injecting a predicted amount of fuel given the reading from your MAF. The ECU watches the lambda sensors, finds how far the mix is off from target and applies a fuel trim to the injectors to get the mix on target.

Lambda sensors are agnostic of fuel, so if you were to put e85 into a stock car, the ECM would inject fuel assuming its running on gasoline, the lambda sensor would report lean, and the ECM would adjust the fuel trims until the lambda sensor reports its on target. You'd have a 20-30% fuel trim in that scenario.

The Proflex intercepts the signal from the lambda sensors and to the injectors, it adds injection time to the injectors and watches the signal from the lambda sensor. It then generates signals that feed back to the ECM so that the stock ECM thinks that the fuel mixture is on target earlier than it actually is. It just fudges the signal from the lambda sensors and then adds extra fuel to the motor so that the stock ECM thinks everything is ok.

The reason I think its worth checking into that is because that proflex directly cuts into the fueling feedback loop. If there is any error at all in it it will immediately manifest in the fuel trims.

Your intake and TB are additional wrenches thrown into this but the right way to go about this is to just remove one at a time and see if the issue goes away.

 

[honeybadger]

I think i can explain why I think its the proflex and it will help you debug.
The system targets a lambda, value The ECU is injecting a predicted amount of fuel given the reading from your MAF. The ECU watches the lambda sensors, finds how far the mix is off from target and applies a fuel trim to the injectors to get the mix on target.

Lambda sensors are agnostic of fuel, so if you were to put e85 into a stock car, the ECM would inject fuel assuming its running on gasoline, the lambda sensor would report lean, and the ECM would adjust the fuel trims until the lambda sensor reports its on target. You'd have a 20-30% fuel trim in that scenario.

The Proflex intercepts the signal from the lambda sensors and to the injectors, it adds injection time to the injectors and watches the signal from the lambda sensor. It then generates signals that feed back to the ECM so that the stock ECM thinks that the fuel mixture is on target earlier than it actually is. It just fudges the signal from the lambda sensors and then adds extra fuel to the motor so that the stock ECM thinks everything is ok.

The reason I think its worth checking into that is because that proflex directly cuts into the fueling feedback loop. If there is any error at all in it it will immediately manifest in the fuel trims.

Your intake and TB are additional wrenches thrown into this but the right way to go about this is to just remove one at a time and see if the issue goes away.

My understanding is that the Proflex only intercepts the injectors at the oem plugs. It's literally intercepting the signal from the ECU and multiplying the pulse width to keep them open longer to get the right amount of fuel. The OEM ECU has no idea this thing is connected and it's not communicating with it at all. It's not measuring lambda or any of that.

 

[junits15]

My understanding is that the Proflex only intercepts the injectors at the oem plugs. It's literally intercepting the signal from the ECU and multiplying the pulse width to keep them open longer to get the right amount of fuel. The OEM ECU has no idea this thing is connected and it's not communicating with it at all. It's not measuring lambda or any of that.

Your right I just checked and it seems like its just going off an assumed injector PW

 

[honeybadger]

Your right I just checked and it seems like its just going off an assumed injector PW

I'd feel a lot better if it was actually reading the lambda sensors. Seems wildly reckless to be adjusting fueling with zero ability to make changes based on how its working. But hey, not my motor

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