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Here's another tip - when you visit a fast food restaurant, don't use the drive thru. Why run the engine at 0MPH when ordering and waiting? I have found that most fast food restaurants are just as fast inside as out. In addition, you can't use the bathroom from the drive thru lane.

Also, what does "FAS" mean? I saw it in several posts and couldn't figure it out.

I just taught a teenager to drive. I stressed following distance (two seconds is hard to maintain) should be such that you never have to use your brakes for small changes in speed. If you're on your breaks frequently other than for stop signs and lights, you're simply following too close.
 

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I taught him both the two second rule and how to tell if you're following two closely via the brake check usage. He knows if someone jumps in front of him he needs to reset his following distance for the new car. I also taught him to watch not only the car in front of him, but also the cars next to him and behind him. If the car behind is too close he knows to back off the car in front. He's also been taught to watch as far in front as he can see - it's amazing how many times you can avoid brake usage simply by noticing that four or five cars in front has tapped their brakes.

For anyone with a teen getting started, I highly recommend having them go through a driving school that does skid pad training (MasterDrive in Denver does). The first time he started sliding on US 6 (Loveland Pass in Colorado) he not only didn't panic but he kept the car in the driving lane. If you're interested in fuel economy, don't let him drive your ECO - the turbo will get a lot of work.
 

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I have played with various shift points during acceleration and have discovered that if the car is below 1300-1400 RPM and I want to accelerate, I actually get better fuel economy by downshifting one gear. The engine torque below 1500 RPM in any gear, especially 4-6, is so poor that you waste a lot of energy. The sweet range for torque with max MPG appears to be 1500 to 1800 RPM. Below 1500 the engine starts to noticebly lug during acceleration and above 1800 the turbo starts engaging.
 

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Florida has actually passed laws that if you are in the left lane, not passing, and others are behind you wanting to pass, you must move over or you can be pulled over and ticketed.
Colorado has the same law for urban interstates. I just wish it was enforced during the non-snow seasons. This would get people into the habit so the white knucklers in the snow would be more likely to stay in the right lane when the road gets wet. 25 under the speed limit on a dry road simply because there is snow on the sides of the road is assinine and should result in a ticket.
 

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I shift into 6th around 41-42.
Is that stock? My comfortable shift point for 6th is 45. Any lower and I lug the engine. My ECO MT is stock tuned.
 

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Define "lug the engine." What exactly do you mean by that?
If I'm accelerating or going uphill shifting up to any gear that drops my RPM below 1500 not only kills acceleration but it also kills mpg. Unlike a carbureted engine, you don't fell the engine straining (lug), but the effect is the same. When I'm running at a steady speed on flat or downhill I can be in 6th at 35 mph without problems.
 

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The stock tune definitely doesn't like moderate to hard acceleration below 1400 RPM. I tested this on the way home yesterday and again on the way to work this morning to rule out temperature differences. Light acceleration at any RPM abouve 1100 seems to be ok. Moderate to hard acceleration below 1400 and the car shivers (like we do when cold). By downshifting I can get the car to stop shivering and also accelerate. I understand your comment that the instant mpg readout isn't very accurate during hard acceleration, but I have also noticed that it runs about the same or a little lower when the engine is lugging vs. downshifting to accelerate. The instant mpg reading certainly stays lower for a lot longer if I don't downshift.

This tank is Shell 89 octane, but I noticed the lug on Shell 91 as well and I had the A/C off for this testing.
 

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Every time I've tried to keep my RPMs above 1500 while accelerating, my total average has been lower.
I follow the acceleration fuel economy guidance BMW came out with when they released a V6 that shut off the injectors to 3 cylinders when not needed for power.

BMW's advice was to accelerate moderately but keep the RPMs below 3000 (Red line on that car was 6,000 RPM). BMW engineers discovered that it's more efficient to get to speed quickly as long as you're not sucking down excessive amounts of fuel while accelerating. For the ECO MT, this seems to work out to flat ground shift at 2000 RPM from 1st to 2nd and 2nd to 3rd and then shift at 1800 RPM for the remaining gears, thus keeping the turbo out of the equation starting in 3rd gear. Shifting before 2000 RPM when coming out of 1st and 2nd appears to drop the RPMs enough that the engine doesn't have enough torque to continue accelerating.

Up hill requires higher shift points to maintain acceleration after the shift. Sometimes significantly higher shift points are required for steep hills, thus keeping the turbo engaged as much as possible. My commute has a valley with a stop light at the bottom. I can't even shift to 6th until I completely climb out of this valley, even though in one direction the speed limit is 65 and the other is 55. When accelerating down hill you can shift at 1500 - 1600 RPM which is as soon as the next gear up won't force the RPMs down to idle or lower. This car really really hates dropping the RPM below idle and will actually attempt to accelerate back to idle.
 

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Your driving style isn't too different from mine. I'd say the differences are minimal. Here are my shift points

1-2: 2000 RPM
2-3: 1800-2000RPM
3-4: 1500RPM
4-5: 1500RPM
5-6: 1500RPM

With the intake resonator removed and the K&N panel filter in there, I can start to distinctly hear the turbo at around 1500RPM, which means it's probably creating a good amount boost around 1400, maybe as low as 1300 or 1350.
It appears we shift the same for 1-2 and 2-3. I can get away with 1800 in the 2-3 unless I'm trying to get up to speed quickly. The remaining shifts I do at 1800. I wonder if altitude is making a difference for these shifts? I live at 5,700 ft. I'll experiment and see if I can get my shift points down to 1500 without becoming a traffic hazard or lugging the engine.

When I shift from 1-2 and I'm accelerating hard I notice that my tach continues to climb about 300-400 additional RPM before dropping. This would explain the 1st gear RPM limiter discovered by the Road & Track reviewer being 400 RPM lower than 2 - 6. Do you see the same thing?

It's interesting that the turbo starts at 1500 RPM but I don't feel it until I hit 1800. I wonder if that's due to time it takes to spin up to be useful. If the turbo is really starting at 1500 RPM that tells me that the optimum flat ground speed for the ECO MT for fuel economy is 45 MPH, which is 1500 RPM.
 

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Nice thread at CleanMPG forums. Wayne had a pre-release model on top of it.

I tried shifting at the RPMs you shift at. That's a no-go at altitude with one exception - stop & go traffic. Turns out the Cruze ECO MT is really good at pulse & coast. I didn't top 1800 RPM the entire time and most of my shifts were at 1500, even 1-2. When I did take it up to 1800 I didn't shift; I simply coasted until I caught up with the next bottleneck in the road taking advantage of DFCO and avoided my brakes for a large part of the commute.
 

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Thanks for the write up. I'll practice some of these. I've been practicing these techniques with my bike.

One technique I notice you didn't mention was Pulse and Glide. Read it and you'll get even better milage.

Driving technique: exploring 'Pulse and Glide' - MetroMPG.com
Pulse & Glide is really useful in the stop & go traffic of rush hour and somewhat useful if you're alone (both no other vechicles or passengers) on the open road. In rush hour you can do pulse & glide simply by not flooring it everytime traffic starts moving. What I have discovered with the ECO MT is that once you're in 6th gear the car automatically pulses up hills and DFCO glides down hills. I wouldn't recomment pulse & glide in any other circumstances unless your passenger is Wayne from CleanMPG.com. It's unusual enough that most people will get frustrated with you because they won't understand what you're doing.
 

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I thought it was common sense not to tailgate people and floor the gas every time traffic gets moving during rush hour. I usually keep nearly 10 cars' distance away from the car in front of me and keep a steady speed. They speed up, they brake, they repeat, and I'm still moving at a steady speed without needing to accelerate.
You couldn't tell it by watching the drivers in Denver. They all seem to think if you're more than 3 feet behind the car in front of you that you're blocking traffic. I've actually had some SUVs get really pissed that I won't pull to the right lane and cut someone in the right lane off until they realize that I always catch the traffic in front of me when the next bottleneck appears. If there's a reasonable gap I'll pull over. The problem on a two lane freeway is the right lane is always stopped for on-merging traffic.
 

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One thing I noticed today while scanning with Torque is something I had suspected. The car tends to drive itself with regard to throttle position. I'll verify this with a few more scans, but I tested this earlier today while going 45mph in 6th gear. I floored the gas and watched the recorded throttle position in Torque and it didn't go past 51%. If I downshifted and allows RPMs to rise, I would indeed be able to hit higher throttle positions. I wonder if the PCM ignores the fact that you're flooring the gas at very low RPMs in a high gear. Perhaps the engineers thought that if you needed to floor the gas, you should be in a lower gear anyway.
Think about what happens in a carbeurated engine (no computer control). If you floor the accelerator pedal at low RPM you feed more fuel in than can be properly burned and can actually flood the engine while moving. Having the ECU control the injectors to prevent this makes a lot of sense.
 

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I can definitely report that high speed mountain driving over I-70 doesn't have that much of an impact on fuel economy. Drove from Denver to Rifle Falls State Park and back today. This drive goes over two passes (actually through a tunnel under one at 10,000 ft) and my pump to pump MPG for the out and back was 47.3 MPG. The DIC read 49.8 MPG. My actual MPG was somewhere in-between, but since first click-off was almost a gallon less than I put in the tank when I got back, I suspect it was closer to 49 MPG. Total distance was over 400 miles and average speed was over 50 MPH. I went over Vail Pass and through the Eisenhower/Johnson tunnels twice. Vail pass is at 10,500 ft and is the highest point on the US Interstate system. The Eisenhower/Johnson tunnels are just under 10,000 ft. Speed limits on this stretch of I-70 range from 65 to 75 except for the Glenwood Canyon section, which is 50 but everyone was doing 55. Other than Glenwood Canyon traffic was moving 2-3 over the posted speed limit. I set my Cruze control at the posted speed limit or 55, whichever was higher.

A couple of observations about the Cruze's 1.4T engine.

First, the non-ECO MT should be able to do this without ever downshifting to 5th gear. I make this claim based on the fact the ECO MT 5th gear is almost identical to the non-ECO MT's 6th gear and that I didn't need to downshift below 5th gear except when slowing down for traffic on the way back. Most of the time I was in 6th gear, even going uphill. There are a few steep hills (west immediately out of Denver, Georgetown hill westbound, the top of the Eisenhower tunnel approaches, and Vail Pass in both directions) that required 5th gear. The car was at 2300 RPM while in 5th.

Second, the ECO MT doesn't engine brake, even at 4500 RPM in 3rd gear. I still had to use the brakes to keep the speed down. I wasn't worried about the car's ability to handle the curves but simply didn't want to be flying down the side of a mountain so fast that the local and state troopers would want to give me a second look.
 

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No, but I can't say I've seen enough members seeing a significant increase in fuel economy to warrant adding it as a tip. Just my thoughts.
I would add this as a possible method to avoid paying for higher octane gas. Several members have reported it seems to help at the low end of the RPM range, which means those of use with the MT may be able to run the engine in the next gear up, which will definitely improve fuel economy.
 

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Overall a great post i think. I will disagree with you over fuel though. I fill up my 1.8li with 87 octane around town but i always use 93 when taking a road trip. Doing my own bits and pieces of research, when driving highway for 4 + hours, i get better gas mileage from the higher octane rating. When i say better mileage, i am talking about 30 to 40 miles per tank more than if i took the same trip using 87 octane. Not sure what it is, or about any of the scientific data, all i can comment on is what i have observed.
What octane to use has been chewed up and spit out in several threads on this forum. The consensus seems to be for each driver to do their own testing as some appear happy at 87, some at 89, and some at 91. The only question I have is does the 30-40 additional miles you get cover the additional per gallon cost of the fuel. If not its not worth it.
 

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Yea. You can mad all you want and even tailgate me. But if the speed limit is met im gonna just keep brake checking.
On multi-lane roads, stay out of the left lane unless you're passing or you have a left exit coming up. This is common courtesy and it also reduces the amount of road rage out there.
 

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...yesterday afternoon, the wife & I were driving back from the grocery store on a rural two-lane, no-passing, road, when what should we see, but a black, lowered and fart-canned, Honda coupe going 30 mph in a posted 45 MPH zone. Wife counted at least six cars stacked up behind US and we were a car behind the Honda.

...guess, he was afraid the rural "bumps" might bottom-out and hurt his jumping-Jack rice-mobile or something?!?

...AZ has a law that on two-lane rural roads, that vehicles impeding track by more than four-deep vehicles must pull over and let the backed up traffic pass.
Colorado's is 6 cars, but it's never enforced. I suspect AZ doesn't enforce theirs either. Sometimes I would really like to be in a monster truck and just drive over these idiots.

My favorite one is the 20 mph in a 55 or better zone when it's snowing and nothing has accumulated yet.
 

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Back to topic -

My neighbor loaned me his Bluetooth ODBII adapter and I downloaded the Torque Lite application to my android phone. Today I monitored both boost and Knock Retard and discovered that the turbo boost really starts to kick in at 1700 RPM, but that there appears to be boost as soon as I touch the throttle. The other thing I noticed is that as soon as my car switched to closed loop mode, the KR jumped to 15 so I'm assuming that is actually my zero point. KR didn't change even going up the hill that used to give the car fits. Outside temperature was 90 today.

Based on this I won't be spending the additional 15 cents/gallon for 91 octane over 89. I still need to test 87 octane after the regap. Maybe I'll compute when I need to fill with 85 to bring the overall octane down to 87.
 

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My "12 ECO MT loses 10+ mpg with the a/c on
Running steady, observe the DIC, turn on the a/c, note the mpg drop on your vehicle.
I'd have your car's A/C checked. Mine doesn't even flinch when switching the A/C on and off. I'm sure there is a difference but it's overwhelmed by the hills around here.
 
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