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As many times as I've re-read that article, I don't understand how it can possibly consume more fuel at idle than it would when in gear and the rpm's are up higher. You would think lower rpm's less fuel, more rpm's more fuel is added. Plus, the ECU adjusts how much fuel is needed at certain rpm's. In the article they talk about pulse width and it going to 0, well then only time it really should be 0 is when the engine isn't running. Otherwise, it's 1 or higher. And in the article they state: Some small cars with roller cams may do slightly better. The article is almost 3 years old. The technology going into cars these days has me wonder what they have done to electrical, fuel and exhaust components to make cars get better fuel mileage and still deliver performance such as the ST with ecoboost.
You assume fuel consumption corresponds to rpm - in reality, it depends on throttle position. You can be coasting downhill at 5,000 rpm, but if the throttle plate is closed, there's no air and thus no fuel. Cylinders are going up and down because the transmission is spinning the engine, but there's no fuel. When you put in the clutch, there's nothing to spin the engine, so you have to burn fuel to keep it from stalling.
 

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If I thought more data would help I'd find and send you more. The article you sent, and we all read, was pretty clear from Popular Mechanics. If you drive ANYTHING with instant fuel consumption on the onboard computer, you'll see as soon as you let off the gas to coast in gear it will show you are using essentially no fuel. Some cars show 99.9mpg when you do this (my last MS3 did this). Some show dashes. But the point is clear. When coasting in gear you're using very little gas.

The irony for me is you learned to do this on a GT. The car that broke me of the habit of coasting in neutral was a 95 GT! The damn thing woudn't go into gear quickly from neutral!
I can confirm this. I have a Scanguage II connected to my OBD port at all times. When my car is coasting in neutral it reads around 2 L/100 km. When I'm coasting in gear, it reads 0 L/100 km.

I can see SJC96GT's point though. When you're in gear and coasting, you may not necessarily be coasting that far, because of compression slow-down, before you have to step on the gas again (and start consuming gas again). Being in neutral allows you to coast much further.

My solution to all this? Simple! Coast while in a high gear! That will allow you to take advantage of the throttle cut-off and minimize engine braking!

Regards,
Andrew

Sent from my Nexus 4 using FocusSTorg
 

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Back roads at 65ish nets me 26ish mpg when I'm nice. Honk on it a bit and I see 23ish. Have yet to see a 4 lane, so no idea.
 

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You assume fuel consumption corresponds to rpm - in reality, it depends on throttle position. You can be coasting downhill at 5,000 rpm, but if the throttle plate is closed, there's no air and thus no fuel. Cylinders are going up and down because the transmission is spinning the engine, but there's no fuel. When you put in the clutch, there's nothing to spin the engine, so you have to burn fuel to keep it from stalling.
As ajwan stated: My solution to all this? Simple! Coast while in a high gear! That will allow you to take advantage of the throttle cut-off and minimize engine braking!

I will try this and see what difference I get compared to when I coast in neutral. I know I won't be able to coast as far in gear compared to in neutral but we'll see what results I get while staying in gear.
 

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Geez guys, there's no reason to get fancy just so you can coast in gear. As you drive, just keep it between 1-2k rpm - when the revs hit 1k, just blip the throttle and downshift so you only use gas for a brief moment... no engine braking, no high revs, just minimize your time with the clutch in.
 

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I've got about 400 miles on mine and on my second tank of fuel. First tank was like 23 MPG. Now I'm up to around 28 MPG. Figuring the third tank I might see 29-30 MPG. Similar to my JCW MINI Cooper S.
 

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I've kept a trip mpg for the life of the car and the tank. After 2000 miles I've got 24.5 on the lifetime mpg (obviously combined mpg) and my last tank I was at 26.5 because of a 60 mile all highway round trip in the middle. I would say it has balanced mpg for being so fun. There's better mpg and it's pretty hard to stay out of the gas and turbo with this thing but all in all it's probably the best car for me, and I'm in your exact situation getting this car for college graduation. I pay everything else and it's a great choice if you're in this position. Obviously a titanium focus or maybe a diesel VW (yuck) would be better on fuel. I'm not ready to give up hauling ass while still having practicality and quirkiness :p
 

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I recently returned from my first extended trip. I was able to get just over 30 mpg while averaging about 75 mph. Given that 6th gear is not an overdrive gear, that's not too bad. I find that I get around 20 mpg around town, and about 23 mpg in my typical combined driving. Being able to run regular unleaded is a nice plus, keeping my fuel costs down.
 

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Ok, thanks! Sometimes the EPA estimates can be a bit off, so I thought I'd ask. Even 24-26 mpg is pretty good for a car like this

Thanks for the replies guys!
Check my Fuelly stats in my sig. My commute is about 75% city and I still drive spirited and I have been averaging around 26mpg.
 

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Real World Gas Milage

I'd just like to see some facts as the injectors shutting off for the car to pass whatever emissions test. Also, how isn't what I stated about being in a higher gear such as 6th gear not true or a fact?lol Being in 6th gear at 55-60 mph will not accelerate you quick enough out of any situation where you need to accelerate very quickly. The fact is you have to be in a lower gear to accelerate quickly or else you're SOL. Whether I be in neutral or 6th gear, I'm still going to have to go into a gear lower to accelerate quickly. The fact is in an ST being in 3rd or 4th gear at 55-60 mph will accelerate you much more quickly than you being in 6th. Therefore if you are traveling in 6th conserving fuel and you need to accelerate for whatever reason you are going to have to downshift to accelerate out of the way quickly, fact. Now unless you're already having fun and in a hard pulling gear you won't need to shift what-so-ever and will have that acceleration needed immediately.
A couple of facts.

The ST will out accelerate in 6th gear a typical 2.0 naturally aspirated car in 3 or 4th. This one of the advantages of having a car like the ST, you can accelerate without down shifting.

If you are truly a defensive driver (everyone should be) you will be anticipating what the traffic around might do and be taking appropriate action. If you do then sat second acceleration is not important.
 

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I believe fuel cut-off occurs ONLY if the motor is turning over above a certain RPM. This depends on the engine/manufacturer designs spec. From what I can tell from my Scanguage, on the ST this occurs around 2000 RPM.

As for me, there are times I coast in neutral and times I coast in gear. Just depends on my mood.

Regards,
Andrew
 

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I believe fuel cut-off occurs ONLY if the motor is turning over above a certain RPM. This depends on the engine/manufacturer designs spec. From what I can tell from my Scanguage, on the ST this occurs around 2000 RPM.

As for me, there are times I coast in neutral and times I coast in gear. Just depends on my mood.

Regards,
Andrew
It's actually more around 1,000 RPM. Put the car in 1st, accelerate, then coast down, and you can feel/ hear when the car cuts off fuel and starts back again. If you're coasting on level ground at ~5mph, that little bit of fuel can actually keep the car rolling.
 

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I believe the manual states to not let the RPM drop below 1,300 which will lug the engine.

While coasting in gear, I never let my RPM drop below 1,500.
 

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I believe the manual states to not let the RPM drop below 1,300 which will lug the engine.

While coasting in gear, I never let my RPM drop below 1,500.
If we're talking about lugging the engine, usually there's some load associated. If you're at 1,200 rpm and you floor it, that's a buttload of stress on the lower portion of the engine (rods, crank, etc.). If you're just coasting at 1,200 rpm there's not really load - but the second you push the accelerator, the cluster display is going to give you a downshift arrow.
 

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A couple of facts.

The ST will out accelerate in 6th gear a typical 2.0 naturally aspirated car in 3 or 4th. This one of the advantages of having a car like the ST, you can accelerate without down shifting.

If you are truly a defensive driver (everyone should be) you will be anticipating what the traffic around might do and be taking appropriate action. If you do then sat second acceleration is not important.
At 55-60 mph?lol I don't know about that, a naturally aspirated car such as a Honda s2000 in 3rd or 4th will for sure out run the ST if you stay in 6th. Now if we drop the ST into 3rd that's when we'll have a bunch of get up and go haha I am a defensive driver/aggressive driver when I need to be. Really, it all comes down to if you follow the distance you are really supposed to follow a car, which is 7 car lengths I believe (been awhile since I read the book). Or whether you see a deer in time to brake hard. (In that case I'd want to be in neutral so I can put as much pressure on the brake pedal as possible) I haven't see or heard of too many people having to accelerate to get out of the way of a vehicle other than maybe a rig not seeing you on the freeway and almost cutting you off. Then at that moment you'd need to accelerate. Unless you're near the back of the trailer then you should brake hard in order to avoid an accident.
 

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At 55-60 mph?lol I don't know about that, a naturally aspirated car such as a Honda s2000 in 3rd or 4th will for sure out run the ST if you stay in 6th. Now if we drop the ST into 3rd that's when we'll have a bunch of get up and go haha I am a defensive driver/aggressive driver when I need to be. Really, it all comes down to if you follow the distance you are really supposed to follow a car, which is 7 car lengths I believe (been awhile since I read the book). Or whether you see a deer in time to brake hard. (In that case I'd want to be in neutral so I can put as much pressure on the brake pedal as possible) I haven't see or heard of too many people having to accelerate to get out of the way of a vehicle other than maybe a rig not seeing you on the freeway and almost cutting you off. Then at that moment you'd need to accelerate. Unless you're near the back of the trailer then you should brake hard in order to avoid an accident.
reminds me when I was racing a neon across the Philly bridge. damn tractor trailer saw me then swerved over to me. upgraded brakes helped out big time
 

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An S2000 is not a typical 2.0 naturally aspirated engine. I am talking about all the Foci, Corollas, Subarus, M3s and cars of that category.

BTW, the proper following distance is a minimum of 2 seconds. The two second rule will create a larger gap as your speed increases. If you have to think about what the proper following distance you are not a defensive driver, it should be automatic.
 

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reminds me when I was racing a neon across the Philly bridge. damn tractor trailer saw me then swerved over to me. upgraded brakes helped out big time
This is a perfect example of not being a defensive driver. Racing on a public road is not a good idea and doing with traffic around is idiotic.
 
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