Optimum shift points

[crozier1]

I have an 07 aveo sedan with a five speed manual. I notice this car does not have a shift light. So my question to you fuel mileage junkies is ..... what are the best shift points for optimum fuel mileage?

[daug1502]

Shift lights are never accurate anyway. Just listen to the motor, when it levels off is the best time to shift. As for mileage, just go to a higher gear than you might need. In flat areas my aveo hatch goes along fine in 4th gear at around 25-30MPH.

[crozier1]

I was just wondering cause i ordered a ultra gauge and was going to set it like a shift light for best mileage. I think you can set them to where they will beep at you if you exceed a certain rpm or engine load. Thats kinda what i had in mind. What do you think about that?

[ontarian_frog]

Key to higher mpg is keeping the engine load high and the rpms low. That means:

1. When cruising, always shift up when you can. I found the Aveo can cruise in 5th gear at 30-35mph no problem.

2. When accelerating, use more throttle, but shift earlier. That doesn't mean to accelerate like a bat out of hell. It means to keep the rpms low enough that you feel the engine loading. When the car starts accelerating faster (lower engine load), shift to make the engine load higher.

3. Coast longer in gear instead of always braking at the last minute. When coasting in gear, the ECU shuts off the injectors and you're moving for free. That means keeping more distance between you and the car in front of you.

There's a lot more you can do for better gas mileage. But I feel this is a good starting point.

[crozier1]

Im defiantly going to give that a try. Thanks foe the input.

[crozier1]

I think with the ultra gauge you can set an alarm where ever you want. I will do some testing ans see where the load begins to drop off during acceleration and set the alarm there.

[ontarian_frog]

I think with the ultra gauge you can set an alarm where ever you want. I will do some testing ans see where the load begins to drop off during acceleration and set the alarm there.

I think that's the better way to do it. It's not perfect, but at least it'll adapt to hills and such. It's a step above just an rpm light. But it's also harder to setup. Here is an article that is pretty interesting on the subject:

Part I & Part II

[Jet321]

Key to higher mpg is keeping the engine load high and the rpms low. That means:

1. When cruising, always shift up when you can. I found the Aveo can cruise in 5th gear at 30-35mph no problem.

2. When accelerating, use more throttle, but shift earlier. That doesn't mean to accelerate like a bat out of hell. It means to keep the rpms low enough that you feel the engine loading. When the car starts accelerating faster (lower engine load), shift to make the engine load higher.

3. Coast longer in gear instead of always braking at the last minute. When coasting in gear, the ECU shuts off the injectors and you're moving for free. That means keeping more distance between you and the car in front of you.

There's a lot more you can do for better gas mileage. But I feel this is a good starting point.

I live in a hilly area, I my my car into neutral a lot, is that a good idea? (manual btw)

[ontarian_frog]

No harm done. You'd probably get a little bit better mileage by leaving it in gear and letting the ecu shut off the injectors.

[JPD]

I have a manual Aveo and use a Scan Gauge e to see when the ECU shuts off the fuel injectors. I don't know whether this saves more fuel than coasting in neutral because coasting in gear causes you to decelerate and you could coast farther in neutral. I read on the ecomodder forum about 'pulse and glide' where the engine is shut off either through a kill switch or in some cars like the Prius automatically if the gas pedal is released under 40mpg. I experimented engine-off rolling on a deserted stretch of road in the Aveo and discovered that 1) I don't know what I'm doing and 2) I shouldn't do it again. The brakes work for a short time and then stop working (must be hydraulic or something) and turning off the engine completely locks the wheel.
Lesson learnt; coast in gear to save fuel.