View Full Version : What's Up With This?

11-12-2013, 03:46 AM
For the first 40,000 miles on my 2012 Rosso Sport Piccollo Mostro he averaged 37.5 MPG regardless of whether it was city, highway, driving like a jack-rabbit or like an old gramps in his '56 Ford F-100 pickup watching the corn grow. Three weeks ago I did a 2400 mile round trip to Indiana and back from Denver and since I got back he is getting 29 MPG. What's up with that?! I'm even overdoing it with the hyper-mileage style of coasting down long hills and up to stop lights and it's still sub-30. This is weird. Anyone else have a drastic overnight change in mileage like that?:apologetic:

11-12-2013, 05:07 AM
A switch to winter fuel type, along with some things related to cold weather and shorter days can account for lower mileage. You're probably seeing lower average operating temperatures, greater average electrical loads, more rolling resistance, tire pressure drop, increased average oil viscosity. You may be seeing longer warmup periods and idling longer.

Robert Nixon
11-12-2013, 10:53 AM
I'm no mechanic, but here are two thoughts:
1: Is there any way the trip to the flatlands and then back up to 5,000 elevation has thrown off your fuel/air mix that the computer is not adjusting for?
2: Did you get a spark plug change back around 30 or 32K miles? I think that's when it's due on the FIATs, just thinking an old spark plug may be reducing power?

11-12-2013, 11:13 AM
40,000 miles check the spark plugs if they haven't been checked already I doubt they have gone bad at 40k in a non turbo car but hey never can tell.

11-12-2013, 11:38 AM
The FIAT recommended 30K service calls for replacing the plugs.

I would also suspect winter or higher ethanol content fuel as well as elevation playing a factor.

12-05-2013, 01:01 PM
I think you might have nailed it with the change in elevation thing. I am now "back home again in Indiana" and he is getting 36+ mpg. I haven't changed driving style at all.

Robert Nixon
12-05-2013, 01:44 PM
plus it's like uphill all the way from IN to CO!!!!:cool