How could I lose 10 mpg in a week of BETTER driving?!

[Jyden]

Originally Posted by Atheria

So during this morning's 22-23 mile cold commute, after finally finding the current time avg mpg sensor, Sophia was getting up to 48! I ended up mostly in the 45-46 mpg range. My car has a mind of her own...but don't all women? ;-) What IS different between my Fiat Sophia and 08 Scion xD named Bob, is that with Bob the mpg sensor would jump to 99.9 if I coasted in gear, but if I do that with Sophia the RPMs stay up and the mpg doesn't improve. My mpg only goes up coasting in neutral. She is not a turbo, FYI.

I'm curious about my next fill up.

Thanks all!
Atheria

What else to expect? Italian ladies has a temperament of their own!
But keep them tires aired up, use the right gasoline, and treat her kindly.

[RobertISaar]

almost every GM vehicle since ~1985 has had DFCO....

can't speak for other manufacturers.

[rmay635703]

A new car requires a breakin period and at least 10 fillups to get any type of idea of what fuel economy to expect during the rest of the breakin period.

Next get a decent economy gauge and be patient, your tank to tank can vary a lot depending on how big the fill was, your driving conditions, speed distance and weather. Drive gentle but too fast (mph) and you FE drops, drive agressive and slow with lots of coasting and it may well go up. If you have lots of stops expect it to go down a lot.

So in other words nothing to worry about, a scangage or the like helps but a new car takes a while to settle in.

Cheers
Ryan

[gone-ot]

Originally Posted by Atheria

So during this morning's 22-23 mile cold commute, after finally finding the current time avg mpg sensor, Sophia was getting up to 48! I ended up mostly in the 45-46 mpg range. My car has a mind of her own...but don't all women? ;-) What IS different between my Fiat Sophia and 08 Scion xD named Bob, is that with Bob the mpg sensor would jump to 99.9 if I coasted in gear, but if I do that with Sophia the RPMs stay up and the mpg doesn't improve. My mpg only goes up coasting in neutral. She is not a turbo, FYI.

I'm curious about my next fill up.

Thanks all!
Atheria

...yes, your Fiat has a built-in MPG display, but notice that you have NO way of calibrating its values, which is the major reason people here keep metioning that you should consider getting a separate fuel economy guage, such as ScanGaugeII™ or UltraGauge™ or similar.

These devices (like your Scion) will jump to 99.9 mpg when you coast, but ONLY *IF* the Fiat computer goes into Deceleration Fuel Cut-Off (DFCO) mode...which it might NOT be doing.

[Atheria]

Well, if my avg. mpg sensor is accurate, by the end of today I was getting 44.9 mpg. I clearly gain mpg by coasting in neutral. It's odd how the RPMs don't drop at all when I take my foot off the gas in gear. I'm also going into the highest gear possible without making the engine struggle. I was in 5th gear today doing just 45 mph.

Thanks again, everyone!
Atheria

[UltArc]

Originally Posted by Atheria

Well, if my avg. mpg sensor is accurate, by the end of today I was getting 44.9 mpg. I clearly gain mpg by coasting in neutral. It's odd how the RPMs don't drop at all when I take my foot off the gas in gear. I'm also going into the highest gear possible without making the engine struggle. I was in 5th gear today doing just 45 mph.

Thanks again, everyone!
Atheria

If I hold a gear without throttle, I slow down more than clutch in. DFCO occurs, but it's engine braking...

If I am not accelerating, I am rarely in gear clutch out.

-All of these points here make sense. I, personally, would not get worried until a few thousand miles. Things have to settle, and that will really show how it will be...pre modification.

[H-Man]

Originally Posted by Atheria

Well, if my avg. mpg sensor is accurate, by the end of today I was getting 44.9 mpg. I clearly gain mpg by coasting in neutral. It's odd how the RPMs don't drop at all when I take my foot off the gas in gear. I'm also going into the highest gear possible without making the engine struggle. I was in 5th gear today doing just 45 mph.

Thanks again, everyone!
Atheria

Your engine is linked to the road when in gear, it can't drop in rpm without slipping the clutch.
The Fiat 500 should be 2,360–2,530 lb, you have 3300 in the garage profile for sophia.

[Atheria]

GVWR = 3,300 lbs. Doesn't that mean the car weighs that much? That is on her door.

I guess I should buy one of those ScanGauge thingys. :-)

Fiats come with software you can download onto your computer. You then plug a flash drive into the USB port in your car and transfer your driving information to your computer. The software will critique your driving to tell you what you are doing wrong regarding mileage, etc. I need to try that.

Atheria

[H-Man]

No, it means max weight with load.

[Atheria]

Seriously?! Oh geeze....LOL