jpd80 Posted August 8, 2015 Share Posted August 8, 2015 (edited) All of my results were from using the cruise control. I think I have lead in my toes because when I use the throttle, I just steady increase speed. That happens with a lot of modern Fords I've driven, you have to keep backing out of the throttle to get best fuel economy, completely different to what we were taught with carbed engines. I've found that on undulating roads, cruise control sucks the juice because it cannot anticipate terrain where as a driver can use momentum and energy conservation to get over those routes more economically. Edited August 8, 2015 by jpd80 Quote Link to comment Share on other sites More sharing options...
MadManMoon Posted August 8, 2015 Share Posted August 8, 2015 I think part of that is gearing, though.... I see similar results w/my 2.5L Fusion. There's about a 10% drop off from 70 to 75 (~35 to ~32). Additional OD gears in the new transmissions should bump that up a bit, I would think. Richard, I refuse to accept any anecdotes about your vehicles until you change your profile. You own a 2000 Mercury Sable, which clearly did not come with a 2.5L engine. Nor was it ever called a "Fusion." 1 Quote Link to comment Share on other sites More sharing options...
RichardJensen Posted August 8, 2015 Share Posted August 8, 2015 Richard, I refuse to accept any anecdotes about your vehicles until you change your profile. You own a 2000 Mercury Sable, which clearly did not come with a 2.5L engine. Nor was it ever called a "Fusion." I prefer leaving it as it is in order to sandbag people who make value judgments based on the car I drive 1 Quote Link to comment Share on other sites More sharing options...
Biker16 Posted August 8, 2015 Share Posted August 8, 2015 It actually has less to do with any of that and more to do with the geometric progression of boost in a turbo. You go from light to moderate boost with very minute movements of the throttle, anyone not driving with backing out of the throttle constantly is going to use more fuel. Even using cruise control with an Ecoboost engine will ruin your day. Over time my economy with cruise has gotten much better, but I am driving alot more than I used to. Because my cars are manuals,0 fuel is consumed with 0 throttle, the same with the DCT. Quote Link to comment Share on other sites More sharing options...
fuzzymoomoo Posted August 8, 2015 Share Posted August 8, 2015 Over time my economy with cruise has gotten much better, but I am driving alot more than I used to. Because my cars are manuals,0 fuel is consumed with 0 throttle, the same with the DCT. To be technical, it's not 0 fuel unless you shutdown the engine while in neutral Point taken though. Quote Link to comment Share on other sites More sharing options...
sullynd Posted August 8, 2015 Share Posted August 8, 2015 Because my cars are manuals,0 fuel is consumed with 0 throttle, the same with the DCT. If the engine is running, it is consuming fuel. Doesn't matter if it is a manual, DCT, or other. 1 Quote Link to comment Share on other sites More sharing options...
jpd80 Posted August 9, 2015 Share Posted August 9, 2015 (edited) There's actually a fuel cut on rundown where higher manifold vacuum occurs, the fuel is cutoff and then restarted at lower speeds. The ZF equipped cars in AUS have this feature. Edited August 9, 2015 by jpd80 Quote Link to comment Share on other sites More sharing options...
Biker16 Posted August 9, 2015 Share Posted August 9, 2015 If the engine is running, it is consuming fuel. Doesn't matter if it is a manual, DCT, or other. No throttle, no gas. The engine braking is also used for smart regenerative charging to keep the battery charged. This is different from most automatics because they need the hydraulic pressure from the engine to operate. Later ford have reduced the amount of fuel used during coasting, I forget what that is called. Quote Link to comment Share on other sites More sharing options...
RichardJensen Posted August 9, 2015 Share Posted August 9, 2015 This is different from most automatics because they need the hydraulic pressure from the engine to operate. This patent says nothing about that: http://www.google.com/patents/US4539643 Also, it appears that Ford has had a fuel cut-off on its automatics for at least 7 years: http://www.at.ford.com/news/cn/ArticleArchives/27491.aspx Quote Link to comment Share on other sites More sharing options...
fordmantpw Posted August 9, 2015 Share Posted August 9, 2015 It's call ADFS (not Active Directory File System, akirby), or Active Deceleration Fuel Shutoff. Our Flex has it, and you can definitely tell as it slows you down quite a bit when you take your foot off the gas. I believe the Flex was one of the first vehicles with it. I guess I should have read RJ's link first....would have saved me some typing. Quote Link to comment Share on other sites More sharing options...
YT90SC Posted August 9, 2015 Share Posted August 9, 2015 DFSO is used with automatics and it has been used a lot longer than 7 years.... IF you let off of the accelerator long enough. The "A" got added- for Aggressive- as it cuts fuel as soon as the accelerator is released fully. 1 Quote Link to comment Share on other sites More sharing options...
RichardJensen Posted August 9, 2015 Share Posted August 9, 2015 AFAIK, as long as the engine's spinning, the automatic transmission will operate. 2 Quote Link to comment Share on other sites More sharing options...
focus05 Posted August 9, 2015 Share Posted August 9, 2015 I noticed the cliff with my 2013 Ford Focus. 55-60 mph was the sweet spot. I could get 42-43 mpg all day driving there with low profile tires even. Get to 70, and it was down to 36. Get to 75 and it was down to 34. Get to 80, and I'm at 31, which is not much different than my 2005 Focus was at 80. For the 2012-4 Focus, I'm pretty confident it was the gearing that made the difference. Ford seems to have optimized the gearing for the EPA tests. My guess is that they would model that optimal load points in the rpm band, get the engine there around 60 in top gear for the EPA test and Bob's your uncle. 1 Quote Link to comment Share on other sites More sharing options...
sullynd Posted August 9, 2015 Share Posted August 9, 2015 No throttle, no gas. Please try this experiment and report back. Fill your gas tank. Start car. Allow to run, parked (no throttle), for 24 hours. Report back how much gas is in the tank. 5 Quote Link to comment Share on other sites More sharing options...
YT90SC Posted August 9, 2015 Share Posted August 9, 2015 sullynd, Bikers comments were about ADFSO. Wrong about automatics, right in how it works. There is no fuel delivered off idle, throttle closed as long as there is inertial energy sufficient enough to prevent the crank dropping below idle speed. Quote Link to comment Share on other sites More sharing options...
RichardJensen Posted August 9, 2015 Share Posted August 9, 2015 (edited) Ford seems to have optimized the gearing for the EPA tests. Possibly--but I don't see a meaningful difference between 55/60 and 65/70 on my Fusion, which is also a 6 speed trans (albeit a fully automatic one) designed under the same EPA test regime. Maybe the Focus has a shorter final drive ratio so it feels sportier? Edited August 9, 2015 by RichardJensen Quote Link to comment Share on other sites More sharing options...
Biker16 Posted August 10, 2015 Share Posted August 10, 2015 AFAIK, as long as the engine's spinning, the automatic transmission will operate. I always thought it required hydraulic pressure to hold the chosen gear. It would make sense that when coasting with a locked torque converter the deceleration could provide enough pressure to hold that gear. Quote Link to comment Share on other sites More sharing options...
fuzzymoomoo Posted August 10, 2015 Share Posted August 10, 2015 I always thought it required hydraulic pressure to hold the chosen gear. It would make sense that when coasting with a locked torque converter the deceleration could provide enough pressure to hold that gear.That might be how they used to work, but I think they are using a different, more efficient design. Not sure (outside of the DCT) what that might be. Quote Link to comment Share on other sites More sharing options...
Biker16 Posted August 10, 2015 Share Posted August 10, 2015 I noticed the cliff with my 2013 Ford Focus. 55-60 mph was the sweet spot. I could get 42-43 mpg all day driving there with low profile tires even. Get to 70, and it was down to 36. Get to 75 and it was down to 34. Get to 80, and I'm at 31, which is not much different than my 2005 Focus was at 80. For the 2012-4 Focus, I'm pretty confident it was the gearing that made the difference. Ford seems to have optimized the gearing for the EPA tests. My guess is that they would model that optimal load points in the rpm band, get the engine there around 60 in top gear for the EPA test and Bob's your uncle. I'd bet those large low profile wheels with a very un aerodynamic profile have alot to do with it. The best wheel design for aerodynamics is flat with no holes. Quote Link to comment Share on other sites More sharing options...
YT90SC Posted August 10, 2015 Share Posted August 10, 2015 In any automatic, if coasting down you have the trans input shaft turning the engine, just like a manual. Locked converter is obviously more efficient doing this, but it can do it unlocked as well, albeit it (input shaft) has to be spinning faster unlocked. The pump is splined directly to the hub/shell of the torque convertor. If the engine is spinning, the pump is pumping. It doesn't take much line pressure to keep clutches applied in a low load situation like throttle off. 1 Quote Link to comment Share on other sites More sharing options...
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