Engine Off Coasting annoyance

[Jonathan_ED3]

This tank, since it's "winter" in TX and I don't need my a/c on, I told myself I would try the whole engine off coasting thing to see what the big deal is.

I quickly found out it is very tedious to keep up. I really don't know how you guys stand to do this on a regular basis. I really do commend you. All the hand motions, glancing up and down at the gauge cluster, road etc and such needed to maintain the whole thing and keep the numbers accurate is quite annoying.

The annoyance I found was that when I turn the car to "acc" while coasting, the speedometer loses power which also stops the odometer from ticking. Of course I can turn the ignition immediately back to "ON" to resend power to the speedo, but I have to leave the ignition at "acc" for a second or two before I can switch it back to "on", otherwise the engine never shuts off and all I've really done is lost power to the speedo. Of course, during all this I've lost valuable tenths from my odometer reading.

So even though it may be saving me a miniscule amount of fuel, it won't fully reveal itself in my calculations at the end of this tank.

What do you guys do about this? Do you just not worry about the tenths of miles you lost? That could add up considerably over the course of a tank.

During the remainder of this tank I will continue to shut my car off at traffic lights, but I'm already sick of trying to do it while coasting.

If I try this again in the future I will wire my speedo/VSS to "acc" instead of "on", that way when I'm coasting it will still be adding on the miles without me having to do a bunch of wrist flipping back and forth.

[theholycow]

Those annoyances are all pretty valid, but the extra effort vs. engine-on P&G doesn't bother me much -- otherwise I'm bored anyway. Also, with some practice it gets easier. If you're not comfortable with it you should definitely not do it regardless of how easy or difficult it is for you + your car + your environment.

My odometer keeps running with the engine off, though I wouldn't care if it didn't. I'm saving the gas whether or not it's measured in my MPG calculations.

[Jonathan_ED3]

Maybe I'm being picky, but if I'm going to be going through all the extra effort, I want to be able to calculate just how much the effort is helping my bottom line.

If I daily drove a pre '92 Civic, I would be all over this since they all had cable speedometers and weren't hinged on any 12v power source.

Honestly I would rather jam out to my stereo and just drive gently than doing all these extra motions. My worst tank EVER with this car just driving gently was 36mpg, so I honestly don't have much to complain about.

I'm still going to shut my engine off at stoplights. If I see a measurable increase in my mileage, I will look very heavily into wiring my speedometer to "acc" instead of on, that way I won't lose any mileage if I decide to EOC in the future.

[theholycow]

How long are your coasts? They should be long enough to absorb the time/distance spent keyed off. If they aren't then you're trying too hard and probably won't gain anything anyway; you may need to be more picky and only EOC when you can get a decent length glide.

[dkjones96]

If you get an old car with a cable driven speedo you won't have to worry about it not reading

[JanGeo]

For at amount of time the engine is off you are probably better off just letting it idle. The fuel consumption at idle is very low since you are already in the 40mpg range already. Also in a recent Science Channel program I found out that the cat operates at 1300 F degrees so letting it cool off is not helping with the emissions at all during EOC. I keep my engine running at idle and still see 200-400 mpg during those coasting intervals at 40mph speeds. It still gets me 5 or more MPG added to my 18 mile trips when I coast with the engine on for the last mile of the trip.

[Daveedo]

quick math Q:
How far do you usually travel in the 2 seconds your key is in the acc position? About 50-100feet?

I'd guess it'd probably add up to less than 1/10th of a mile for a normal urban/suburban trip.

Good point though. On the other hand your car will appear to have a few less miles than it actually has on it which is better for resale (although a very small amount)

[theholycow]

60mph is 88 feet per second...

[GasSavers_mikemoss]

During the engine off coasting what do you do about power brakes and steering?

Seems dangerous to be going down the highway with no power brakes or steering. Is it even legal in some states I think it is illegal to coast in neutral, or at least my dad said he got a ticket for doing it once.

[Dalez0r]

Originally Posted by mikemoss

During the engine off coasting what do you do about power brakes and steering?

Seems dangerous to be going down the highway with no power brakes or steering. Is it even legal in some states I think it is illegal to coast in neutral, or at least my dad said he got a ticket for doing it once.

Dont know about your vehicle, but mine has enough brake reserve to last 2-3 pumps of the brakes before I need to worry. And I've never needed power steering on the highway, only at low speeds. As for legality, it varies considerably state to state... thread about this somewhere...