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RCFiat
08-03-2016, 10:19 PM
Just did a 1000 mile drive down to Florida in my 2015 Urbana Trekking automatic.
Extremely comfortable without the leg and knee aches experienced in my recently owned 2015 Jetta and 2013 Mazda 5. (My previous trip in March in my 2015 500 Sport was also ache-free). BUT, the indicated gas mileage has been consistently 10% optimistic. I find that completely unacceptable. My Sport is very accurate, as is my Suzuki SX4. Have others noticed the same thing on their Ls? I asked the dealership down here about it, and was told that they had not addressed this situation on other customer's cars.
On my trip back tomorrow, I will check the odometer as well. I certainly hope that it is not adding miles at a rate of 110%.

Andree
08-03-2016, 11:48 PM
This is how to go about doing a highway mpg test:
http://www.fiat500usaforum.com/showthread.php?18212-Pure-Highway-MPG-Test

You will not be able to do it on the return trip, as you won't be filling up at the same pump.

And what you will be doing is comparing the actual miles driven to the second gas fill up. That should be accurate.

We did have a similar problem in the 2009 Honda Fit. People complaining, but no one taking their cars in. I did take mine in, and the mechanic who did the test, as instructed from Honda, did indeed find a discrepancy between the readout from the cars, and the actual mpg. They then were able to send out a tech bulletin to all Honda service departments, along with a flash update to make the readout more accurate.

Do the test when you get back, and see if there is indeed a huge gap. This is the same thing Fiat service would have to do to document the issue. And they will still probably have to do it on your car, even if you do it yourself. But once done, there is a record, and someone can look into it, make the update, and get any/all other Ls updated too.

Fiat500USA
08-04-2016, 12:26 AM
The fuel economy trip computer is an estimate. Some cars are more accurate than others and I remember reading on Audi World some folks cars were off somewhat from the reality. I believe this could be adjusted in the Audi, so maybe the same could be done on the Fiat. Hopefully when it is adjusted it won't be worse! I can imagine it could take several visits to adjust and may require some patience while it is zeroed in.

While you are measuring, keep in mind that fuel pumps can vary when they turn off so it is good to use the same pump when measuring fuel economy. Even the temperature can make a difference when filling up so these factors can also affect accuracy.

RCFiat
08-04-2016, 08:32 PM
Just back to NC, stopping at my brother's as I did on the way down to FL. My first gas stop back was at the same station in Georgia I typically use, and the second stop at the same station in SC I used on the way down. In both cases, comparing the car's indication to my manual calculation, the discrepancy is just shy of 10%. I also checked the odometer for accuracy, and found that it is actually reading low by .7%. So 31mpg calculated is about 31.2. Still, not close to the car's 34. The dealer in Florida did say that they could possibly run a flash update to see if that makes a difference. Back in Maryland I'll look into that.

The Jetta I traded for the L was also optimistic, though by around 5%. A coworker did say that adjustments could be made on those vehicles, so I'm guessing perhaps the same can be done with Fiat.

When I tallied the 'actual' gas mileage for the 978 miles down, using all gas receipts, the figure came out to 30.7 mpg, or very close to the window sticker's figure of 30. However, the car showed 33.7 mpg for that same distance. So going forward, until and if an adjustment to the car is made, I'll mentally adjust the readout to about 90% of what's shown.

A very comfortable long distance car.

Simmonz
08-05-2016, 10:58 AM
Just back to NC, stopping at my brother's as I did on the way down to FL. My first gas stop back was at the same station in Georgia I typically use, and the second stop at the same station in SC I used on the way down. In both cases, comparing the car's indication to my manual calculation, the discrepancy is just shy of 10%. I also checked the odometer for accuracy, and found that it is actually reading low by .7%. So 31mpg calculated is about 31.2. Still, not close to the car's 34. The dealer in Florida did say that they could possibly run a flash update to see if that makes a difference. Back in Maryland I'll look into that.

The Jetta I traded for the L was also optimistic, though by around 5%. A coworker did say that adjustments could be made on those vehicles, so I'm guessing perhaps the same can be done with Fiat.

When I tallied the 'actual' gas mileage for the 978 miles down, using all gas receipts, the figure came out to 30.7 mpg, or very close to the window sticker's figure of 30. However, the car showed 33.7 mpg for that same distance. So going forward, until and if an adjustment to the car is made, I'll mentally adjust the readout to about 90% of what's shown.

A very comfortable long distance car.

I use Fuelly.com to track the mpgs on my Abarth it comes in very handy. On that note my In car MPG's are always 1 to 3 mpg better than what I'm actually getting.

RCFiat
08-06-2016, 10:00 AM
Back to Washington County Maryland, home of gas price collusion and monopolized distribution.....I've said that about this area for over 4 decades now. So much for $1.78 I was paying down south. We're still at $2.15 for regular, while just over the line in Frederick county, regular is $1.99 at the same brand locations.

Anyway, couple of observations. On my last leg, rather than filling up in Lynchburg, I waited for the rural station near Afton Mountain I had seen on the way down with those low prices. I ended up filling with high test since it was just 30 cents a gallon more. I had not been using high test during the trip. On the leg down to Lynchburg, better conditions than I had on the return, the car had indicated 34.9 mpg, and calculated out to 31.7. On the return leg from Afton, I ended up in Hagerstown indicating 38.5 mpg, which included the aggressive run up Afton Mountain. I figure my hand calculation will come out to around 34.6 when I fill up today. My speed on I-81 was around 73 mph. So, did the high test gas make that big a difference? Maybe. What I have found is that my best mpg does come from Va gas, which may be lower in Ethanol.

But another observation upon my return might be more telling. Since I bought the car, a service loaner which had 2400 miles upon purchase, the tailpipe would get "sooty" very quickly. It was black upon my purchase. I would clean it weekly, and within a few days the build-up would return. When I got to Florida, it was quite bad. I again thoroughly cleaned it the day before I left to return home. The previous day, while in WalMart, I purchased their cheap (97 cents) bottle of fuel injector cleaner and poured 2/3 of that into the full tank. At that stop in Afton, I poured in the rest.

After the nearly 1000 mile return trip (the car now has a total of 5400 miles) the tailpipe was essentially clean. No soot to speak of. Perhaps the injector cleaner did some good. I'll monitor going forward.

fiat500elle
08-25-2016, 11:28 PM
My gas mileage sucks. I went from a Jaguar X-Type with a 3.0 V6 averaging 24MPG on trips around the city (70/30 city/hwy). The 500L struggles to stay above 20MPG on the same routes. This on a car bought with 800 miles on the clock.

Fiat500USA
08-26-2016, 10:16 AM
My gas mileage sucks. I went from a Jaguar X-Type with a 3.0 V6 averaging 24MPG on trips around the city (70/30 city/hwy). The 500L struggles to stay above 20MPG on the same routes. This on a car bought with 800 miles on the clock.


What year and trans do you have? How many miles now? How do you check it? The most accurate way to check is to record the miles/ gallons manually and not use the trip computer. Also when you get gas, do not try to squeeze any more in once it clicks off (providing it didn't turn off prematurely). Fuel economy is dependent on how and where you drive, and there are ways to improve gas mileage if that's important to you, depends on the trans so let us know.

Pionieri Tridentina
08-30-2016, 11:23 AM
Here my MPG experience.
2014 500 L trekking, standard gear, now 28k miles, always use 91 oct, sometimes 89. I'm very familiar with standard driving, never squeeze the 1st hear, if needed the 2nd or 3rd.
Driving in OK-TX-NM, seems that the strong winds affect the MPG a lot.
The average on Interstate driving, 6th gear, cruise control at 70, light winds : 36-39 MPG. At a speed of 65, same condition, 38-40 MPG. Driving on Interstate with our strong headwinds ( 20-30 miles wind ), same conditions as before at 70 the MPG is 29-32.
I came back from Abilene TX two months ago, with 30 miles tail wind, it gave me 42 MPG.
If I drive around 75-80 on Interstate, the MPG is around 26-29.

Seems keeping around 65 MPH or less is an excellent but boring speed to save on gas. I dont count city mileage, all the cars use a lot of gas in stop and go.
P.S. My observations about winds, I'm a pilot, so we look at winds all the time.

nykonos
09-08-2016, 01:09 PM
So i wanted to see how accurate the computer was on my fiat 500L, so i downloaded a gps/mph app on my phone so that i knew there was no error in the calculations. I filled up and i turned on the app every time i drove. Then when i filled up and read how many gallons i used i did the math with the gps miles and i get around 23 miles per gallon. Plus my gps said i drove less miles than the fiats odometer said i drove so my only assumption is that the miles are racking up faster than i drive them. So im going to keep doing this and keep using this and more gps apps to make sure to see how accurate it really is but so far im more inclined to believe that is my actual MPG considering how often i fill up. Anyone else try this? Also who would i call to get them to test this theory and get a recall made?

Lemon Law
09-16-2016, 08:30 PM
I am getting 22.7 mpg but I was getting 30-32 until they did the 1st flash up date now my milage is same as yours and it does not shift right. Do you have shifting problems?

fiat500elle
10-05-2016, 06:56 PM
My gas mileage sucks. I went from a Jaguar X-Type with a 3.0 V6 averaging 24MPG on trips around the city (70/30 city/hwy). The 500L struggles to stay above 20MPG on the same routes. This on a car bought with 800 miles on the clock.

Well, I figured my issue out. The CEL eventually came on and logged a P04DB code. This was odd at first since the car is completely stock.

Upon further inspection I found the 90 degree elbow connecting the crankcase ventilation MAP sensor to the air intake was split. This on a car with less than 4,000 miles on it.


I replaced the elbow and immediately started seeing more power and my gas mileage is now at an all-time high of 26MPG mixed city/hwy!

http://www.fiat500usaforum.com/attachment.php?attachmentid=23759&stc=1

gr8gatzby
11-25-2016, 03:34 AM
I average about a shade under 25mpg with 50/50 driving. Considering that's 100% city numbers, it's fairly disappointing.

fierostetz
11-25-2016, 12:28 PM
So i wanted to see how accurate the computer was on my fiat 500L, so i downloaded a gps/mph app on my phone so that i knew there was no error in the calculations. I filled up and i turned on the app every time i drove. Then when i filled up and read how many gallons i used i did the math with the gps miles and i get around 23 miles per gallon. Plus my gps said i drove less miles than the fiats odometer said i drove so my only assumption is that the miles are racking up faster than i drive them. So im going to keep doing this and keep using this and more gps apps to make sure to see how accurate it really is but so far im more inclined to believe that is my actual MPG considering how often i fill up. Anyone else try this? Also who would i call to get them to test this theory and get a recall made?


Each of my cars has a Mead notebook in it where I record maintenance, each fill-up, topping off oil, date/tire pressure, etc.
The most reliable way I've found is as follows:
- Each time I get gas, it's a complete fill. I document the number of miles driven (per trip-computer 1) and the number of gallons the car took.
- After filling up and recording milage, I reset trip computer 1.
- At the end of each month (or more often if I feel the mileage dropped) I'll go in and divide the number of miles per tank by the amount of gas it took, giving an accurate picture of your mileage.
- Whenever I think of it, I dump the raw data into an Excel spreadsheet and chart it so I can get at-a-glance indications of what sort of mileage I'm averaging, if there are trends, etc.

The averages I get from manually calculating generally indicate the car is 10-12% optimistic in it's mileage figures. Most cars are pretty optimistic, my abarth is about average if perhaps a little more optimistic than my prior cars. My last car, 2010 VW golf with the 2.5 inline 5 was the most accurate mpg calculations I've ever seen, less than a 5% variance over 6 years of mileage.

Americangunner
03-29-2017, 11:46 PM
I get about 28 mpg around town and over 34 mpg if I keep it under 70. About 32 at 80. I have a 2015 500L the only mod is a Gopedal. This is hand calculated. The indicator is normally off by 1 or 2 mpg.

RCFiat
03-30-2017, 09:08 PM
I originated this thread some time back, concerned with the extreme discrepancy between manual calculation of gas mileage versus the car's indication. I also started a thread in which I discussed an increasing oil level. Since both posts, I have continued my investigations. I believe both issues are related. I think I have excess gasoline getting into the crankcase. On my last oil change, my third in 9000 miles, I removed more than 4 quarts of fluid. The additional amount I believe to be gasoline. This would explain the mileage discrepancy. I would be thrilled to get the mileage reported above.

More clues to this mystery is the fact that the exhaust pipe builds up soot quickly. I am cleaning if every week. In addition, I changed the spark plugs, and found two of them to be quite fouled, and the other two also not what I consider normal.

The sad part of all this is that I took the car to a dealer, who kept the car for two days. This was before the last oil change and spark plug replacement. I asked them to check for a leaking fuel injector, to take a look at the plugs, and also pointed out that I get a pasty buildup on the oil cap. They performed no diagnostics whatsoever in that time. Nothing was examined. I was told that they would not open a case since they had not performed any of the maintenance on the car. This from a dealer who had only recently added Fiat to their location.

So, I now wonder. Without a lot of 500ls running around, I have not been able to take a look at the exhaust tip on others. What do other owners experience? A clean exhaust tip as on my 500 Sport, or lots of soot?

fierostetz
04-01-2017, 02:17 AM
my abarth, at least, is pretty sooty

Ducman69
04-01-2017, 03:08 AM
The fuel economy trip computer is an estimate. Some cars are more accurate than others and I remember reading on Audi World some folks cars were off somewhat from the reality.
In theory though, the only way it should be off is if the speed is off, and on my 500 (non-L), the speed is in fact off quite a bit, saying I'm doing 82-83mph when my phone and tablet GPS both say I'm going 80mph.

If I take a trip that is 300 miles long, if the speedo is 3mph off, it would think I went 32 miles further than I really traveled (and yes the odometer would be racking up the miles too).

The reason I say that's the only way its off, unless its designed to read high, is because the ECU has access to extremely hyper accurate MAF and fuel readings accurate to the drop, as otherwise it wouldn't be able to maintain a perfect air-fuel ratio, which my OBD2 scanner says the car usually does. If it knows exactly how many drops of gas its putting into the engine, then it just needs to know how many miles its gone to make an accurate MPG reading.

Now one thing that is normal, is that tires wear down. A brand new tire is much bigger than a completely worn out tire, and that change in circumference will make the speedo read fast.

And here's something really weird. OEM tires for a 500 (non L) is 195/45/16. The optional size is 205/40/17... whats the big deal? They aren't even the same size! The 195/45/16 OEM option will rotate 21 times more per mile than the 205/40/17, which would change the listed fuel economy, listed speed, and odometer since there's no way for the car to know if you have the 16" or 17" optional wheels mounted. So to fix that a little bit at least, I installed 205/45/16s, which is still a tiny bit smaller than the 17" diameter, but not that much.

Ducman69
04-01-2017, 03:17 AM
I think I have excess gasoline getting into the crankcase. On my last oil change, my third in 9000 miles, I removed more than 4 quarts of fluid. The additional amount I believe to be gasoline. This would explain the mileage discrepancy. I would be thrilled to get the mileage reported above.

More clues to this mystery is the fact that the exhaust pipe builds up soot quickly. I am cleaning if every week. In addition, I changed the spark plugs, and found two of them to be quite fouled, and the other two also not what I consider normal.
The soot is normal, a side effect of most turbocharged engines. The gas in the crankcase I think is extremely unlikely. You only have a gallon of oil right? You change your oil at 9,000 miles. In 9,000 miles you would have gone through 300 gallons of gas. How much additional gas could possibly be in your oil? Half a quart? How could that affect your measured fuel economy over 300 gallons? That tiny amount is easily less than human error in measuring fuel economy.

Secondly, even if you got half a quart of gasoline in your oil, you would say "hey, my oil smells like gasoline" because it really would, it would be unusually thin, and your engine would be unusually loud from the very thin oil not lubricating properly.

RCFiat
04-01-2017, 10:34 PM
I've taken two trips to Florida with the car thus far, and the gas mileage discrepancy (manual calculation versus car) during those trips, as well as local driving, continues to be about 7% off, the higher figure being that reported by the car. I also compared the odometer to mileage markers for very long stretches along I-95, in different states, and the car's ODO is essentially right on.
As for the speedometer, yes, both my 500L and 500 Sport read 2 mph fast. The VW Jetta I traded for the L was also 2 mph high. But that is not impacting the accuracy of the odometer.
More comments following your other post.

RCFiat
04-02-2017, 09:56 AM
My first oil change was at 2800 miles. The car had been a service loaner, and had 2400 miles at time of purchase. The dealer was 300 miles from home. At the time the oil was very black, and the filter pleats were black. I did not give it much more thought until after my first trip to Florida. Upon arrival there, I checked the oil, expecting to see a drop, and instead, the level was high on the stick. That remained the case when I got home. The antifreeze level is perfect, so I figured it had to be either gas or condensation. Prior to my second trip to Florida, I changed the oil again at 6250 miles. The next day I changed the oil for the first time on my 500 Sport, with just over 5000 miles on it. The oil filter from the Sport was what was expected, with darkened pleats. The filter from the L was again black, with just over 3000 miles since the prior change.
I was watching very closely on the second trip. Sure enough, the level rose again. That's when I brought the car to my closest dealer, who had the car for two days. I told them about the increasing level, the soot on the tailpipe, and asked them to check for leaking fuel injectors. They sniffed the dipstick in that time, and returned the car to me saying that since they had not serviced the car, they would not open a case. It sounded like they thought I had overfilled the crankcase. So I changed the oil for the third time at 9000 miles, and collected the oil in a marked container. More than 4 quarts of fluid came out. I took pictures of that container, and will attempt to post. The filter again was black.
I changed the spark plugs a couple days later. Lots of fouling on two of them. The other two were also showing some black areas.
Perhaps the plugs and tailpipe are typical of this turbo engine. If so, that's bothersome. I'll check Abarths in my area, and try to run down the other Ls I've seen.
But the rise in oil level cannot be considered normal.
As for noise levels, there have been times when I have 'hammered' the car, once completely warmed up of course. And the aural nature of it is not nearly as smooth as my Sport. Again, is this typical of the turbo? My car is an automatic, unlike everything else I own.