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Holy smokes Altis, you are so wrong about A/C its not even funny.
[rofl] Oh man... ^ times a million.

GoShockers: I do wish I had better than circumstantial for you on this, but I don't have the Scan Gauge. I can tell you that since I stopped coasting to stops in neutral and started coasting in gear I've gained what appears to amount to around 1-2 mpg. Admittedly it's tough for me to say whether this is due to break-in or the coasting adjustment.
 

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[rofl] I do wish I had better than circumstantial for you on this, but I don't have the Scan Gauge. I can tell you that since I stopped coasting to stops in neutral and started coasting in gear I've gained what appears to amount to around 1-2 mpg. Admittedly it's tough for me to say whether this is due to break-in or the coasting adjustment.
I have a scangauge on my 2012. When coasting (foot off of accelerator) in drive the system goes into open loop and shuts down the injectors.
 

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[rofl] Oh man... ^ times a million.

GoShockers: I do wish I had better than circumstantial for you on this, but I don't have the Scan Gauge. I can tell you that since I stopped coasting to stops in neutral and started coasting in gear I've gained what appears to amount to around 1-2 mpg. Admittedly it's tough for me to say whether this is due to break-in or the coasting adjustment.
I'm not sure how you gained anything by not coasting. lol

[wrenchin]
 

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I have a scangauge on my 2012. When coasting (foot off of accelerator) in drive the system goes into open loop and shuts down the injectors.
Right. I was trying to offer some information on what the overall improvement of that really is. It's a fine little bit of knowledge, but if it amounted to 1/20th of an mpg then I wouldn't care. It looks like it's significant, though, at least for my drive.

One other question for you... someone suggested that there might be a cutoff speed where the injectors come back on if you're going too slow? I don't see driving any differently but I am curious. E.g., if you're coasting in gear below 25 MPH then it still feeds the engine fuel?
 

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One other question for you... someone suggested that there might be a cutoff speed where the injectors come back on if you're going too slow? I don't see driving any differently but I am curious. E.g., if you're coasting in gear below 25 MPH then it still feeds the engine fuel?
I have noticed it consistently goes back into closed loop at 25 mph and below. Upon taking your foot off of the accelerator their appears to be about a 2 -3 second delay before it goes into open loop. If you give the accelerator the slightest bit of gas it goes right back into closed loop.

One other thing i have noticed while using the cruise control going down hill is if the transmission downshifts to a lower gear to keep from exceeding the set speed on the cruise control it will also go back into closed loop. So on long steep down hills it may be better to turn off the cruise control to help save fuel.
 

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I have a few friends that are engineers at Ford. One of them is a mechanical engineer working on engines.

I spoke to him at length about Ford's aggressive deceleration fuel shutoff feature. This feature is a perfect complement to the hypermiling technique of "driving without breaks".

The fuel shutoff feature uses more than half-a-dozen variables to calculate when to shutoff the fuel going into the engine. The main three are: throttle position/ brakes applied, engine RPM, and load (A/C, defrost, read window defrost, all other electric current draw: lights, radio). The other variables are items such as engine temp, vehicle speed.

For example, when coasting down from any high-way speed (foot off the gas pedal), or even city road speeds, the engine computer will shut off the gas to the fuel injectors. When the vehicle nears stopping speed (say at a traffic light) the computer then will turn back on fuel to the engine to maintain a minimum of 600 RPM (the standard idle speed). So do not use the Advanced hypermiling techniques of turning off the engine when coasting down a long hill, or even putting the transmission in neutral to coast. The engine computer shuts off fuel (and turns it back on) way faster and safer, than any human could.

The other feature we talked about was the variable valve timing for the two cam shafts. This is not a switch that has two settings: economy or performance. The engine computer can adjust the timing of both the intake and exhaust valves (independently) to provide a (relatively) infinite range of timings as necessary to respond to throttle position. This provides both economy and performance from the same engine. There is no need to use a high octane fuel to attempt modify valve timing for better gas mileage, with the Twin independent variable camshaft timing (Ti-VCT), the engine computer determines the best valve timing. I asked how I could know if the computer was using maximum economy timing, he said there was no way for me to know, he recommended I use the eco-mode in the display.

The other hypermiling item I noticed is that the Tires: Continental contiprocontact, have a maximum 51 psi. I would guess that filling the tires that full would lower the rolling resistance significantly. (I personally would not fill the tires that high during winter/snow season.) The Focus Super Fuel Economy package uses four items to achieve the extra 2 miles per gallon (highway only): low rolling resistance tires, active grill shutter, rear spoiler, and aerodynamic wheel covers. From what I have read, the low rolling resistance tires probably make up 75% of the 2 MPG improvement.

http://media.ford.com/article_display.cfm?article_id=33942
 

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The other hypermiling item I noticed is that the Tires: Continental contiprocontact, have a maximum 51 psi. I would guess that filling the tires that full would lower the rolling resistance significantly. (I personally would not fill the tires that high during winter/snow season.) The Focus Super Fuel Economy package uses four items to achieve the extra 2 miles per gallon (highway only): low rolling resistance tires, active grill shutter, rear spoiler, and aerodynamic wheel covers. From what I have read, the low rolling resistance tires probably make up 75% of the 2 MPG improvement.

http://media.ford.com/article_display.cfm?article_id=33942
At 51 psi, I would imagine that you would lose whatever fuel advantage you gain at that pressure to the cost of replacing the tires early due to wearing the center of the tread prematurely.

The SFE package really only has 3 exclusive items (tires, spoiler, wheel covers) now that the shutters are included on all Focus models after the "Job #2" updates on March 5th.
 

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the active grill shutters and the spoiler are available on other trims, so it really is just the tires and wheel covers that are the difference in the SFE.
 

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From what I have read, the low rolling resistance tires probably make up 75% of the 2 MPG improvement.
Good write-up, thanks. I'm inclined to agree to a great extent about the tires making the biggest difference. I'd be curious to get some kind of official breakdown from Ford. I know it'll depend in part on the kind of driving you do, but, face it, all those aero upgrades aren't going to help that much if you spend most of your drives under 35MPH. The tires will, though.

I do wonder if it's true about the fuel shutoff not being effective under 25mph. If so, for us manual drivers, there's no clear fuel saving benefit to downshifting anything below 4th gear when you're slowing to a stop? I might prefer to wear my brakes down instead of my clutch if that's the case.
 

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At 51 psi, I would imagine that you would lose whatever fuel advantage you gain at that pressure to the cost of replacing the tires early due to wearing the center of the tread prematurely.

The SFE package really only has 3 exclusive items (tires, spoiler, wheel covers) now that the shutters are included on all Focus models after the "Job #2" updates on March 5th.
Not to mention 51psi would probably be a safety concern. Goodbye traction.

My December-2011-built manual has the grille shutters just fyi.
 

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I have a few friends that are engineers at Ford. One of them is a mechanical engineer working on engines.
Hey do you have an engineer friend that knows anything about the DCT? Would be nice to get some inside info on that.

The fuel shutoff feature uses more than half-a-dozen variables to calculate when to shutoff the fuel going into the engine. The main three are: throttle position/ brakes applied, engine RPM, and load (A/C, defrost, read window defrost, all other electric current draw: lights, radio). The other variables are items such as engine temp, vehicle speed.
So sounds like DFSO may never engage if you're running the A/C, listening to the radio and charging you're iPod at the same time. Which is not at all uncommon.
 

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I will be listing one for sale in a few weeks. Don't own any more obdII cars (functioning ones) lol.

BUT about DFCO...... really want to get a good idea? get a wideband. I cant imagine it would be too different but on my 22 year old car, any time the engine is at or near operating temperature, it will cut off fuel as soon as I let off the pedal; load or no load, as long as I have been ON the gas then let off, it will shut off (defaulting the wideband to 22.4:1 afr) It does not do this at idle or cruise as it shouldn't

I'd like you guys to define coasting a bit better with these cars. Can you feel the whole thing slowing down with the engine or does it just coast like it is in neutral?

Wideband has helped me with fuel just a bit.... I have learned not to throw it in neutral and coast but rather keep it in gear to slow down. idle and cruise AFR should be 14.7-15.1. Anything more and it has a chance to burn valves. Under acceleration it can drop to 12 or 13. Deceleration it will default to the max reading which makes it super lean.
 

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BUT about DFCO...... really want to get a good idea? get a wideband. I cant imagine it would be too different but on my 22 year old car, any time the engine is at or near operating temperature, it will cut off fuel as soon as I let off the pedal; load or no load, as long as I have been ON the gas then let off, it will shut off (defaulting the wideband to 22.4:1 afr) It does not do this at idle or cruise as it shouldn't
The 2012 has a UEGO (wideband) as the primary sensor.
 

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BTW, a scangauge isn't necessary to determine open/closed fuel status.

Put the ICD in test mode and monitor FUEL FLOW.
It is a rolling counter. The counting speed is proportional to the fuel consumption. When the count stops, the injectors are off.

Simple, eh?
 

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I'd like you guys to define coasting a bit better with these cars. Can you feel the whole thing slowing down with the engine or does it just coast like it is in neutral?
The car slows with the engine when in gear. We just mean "coasting" as in "foot off the accelerator," whether in neutral or in gear.

With only 5 speeds, the top gear is definitely not a high-speed cruiser and there is a significant "drag" from the engine in 5th if you're going fast and not giving it any gas. It doesn't matter much if you're coming to a stop, but if you're coasting through a lower-speed stretch and plan to speed back up after, coasting in 5th causes quite a lot of momentum loss versus coasting in neutral.

BTW, a scangauge isn't necessary to determine open/closed fuel status.

Put the ICD in test mode and monitor FUEL FLOW.
It is a rolling counter. The counting speed is proportional to the fuel consumption. When the count stops, the injectors are off.

Simple, eh?
It sounds simple but I'm totally unfamiliar with that... :) What is it?
 
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