Searching on the mobile site yielded no results so here is a new thread. Sorry guys!

Mpg last tank 19.08 (fuelly)

So how much gas does the ac use?!?!? To fluctuate 26-19 sucks something large and unpleasant...for that I might as well drive a less economical.

Is there anything I can do or check to combat this and get more consistent tankfuls...

 

If you're getting 19MPG with this engine, unless you're driving everywhere in first gear on purpose, then I'd have to think there is something mechanically wrong with the car. Is your car auto or manual transmission? Have you taken it in for inspection? If it's an auto, perhaps the transmission is failing and it's driving in the wrong gears.

My last tank driving with the AC on all the time I got ~40 mpg combined and I drive hilly country roads for commute and usually push people in front of me up the hills. Of course gas mileage varies due to driving habits and routes you take, etc... but there's no way the tiny anemic engine they put in this car should be giving you 19MPG even if you step on the gas at every stoplight. I really don't know how you guys get under 30 in it, travelling flat road at 65MPH my instant meter never dips below 50.

 

Yeah, I drive with AC at full cold most of the time, mostly short trip driving, heavy foot, etc, and the worst I've gotten is 25 mpg, and that was a one off thing.

For me, the only time I get get to go on a flat road at 65, its ~ .5 mile to the next exit, but involves stopping at a light, then up hill + accelerating to 65 to merge with traffic.

 

On mine that instant meter thing doesn't seem very accurate. Reads 40+ most of my drive. The tank ave, or whatever that meter is called is right on and I get about 30.5 overall.

 

To add I have an auto, and the onboard says I average 26.4 which I accept given my love for 75 mph, driving with the windows open, wider tires and my fat ass. That and for my job I do 10 visits a day with lots of stopping and starting the engine between each.

The fuelly numbers are always lower. The car feels fine and my long term trim is 2-10, rarely negative.

If I idle with the ac on its for about 5-10 minutes.

Could fuelly be off? I thought the math was spot on.

 

It's actually pretty accurate, even a big V8 engine gives you good mileage travelling down the road at 65 MPH because the inertia of the car does most of the work. It's simply reporting what mileage you're getting at that instant.

Average fuel mileage is mostly about acceleration, and how you manage it. If you could manage to travel at 65MPH without actually having to accelerate to get to 65, then you'd get 50MPG. It's the acceleration that takes all the energy and sucks down the gas, not the actual cruising.

Although 75MPH with the windows down is going to add a lot of drag and suck a lot of gas. Using the A/C instead of rolling down windows should give you much better fuel mileage.

 

For average MPG over a tank you simply take the miles driven and divide by total amount you put in the tank. You should reset the trip meter every time and use that number instead of the odometer, it will give you more accurate results. So far I've found the average meter to be pretty accurate.

You may have just entered a number wrong, or reset the trip meter a mile or two down the road without realizing it.

However if you're suddenly getting 19MPG, then there is something wrong with the car. MPG doesn't just drop that much for no reason. How many miles does the car have?

 

on my week old fit, i am doing 35 MPG, and that is with the A/C on most of the time. i'm not doing anything intentional to improve MPG ... still trying to learn manual shift properly. I suspect that the mpg will improve as I learn to shift better.

 

SgtBaxter, before you start suggesting that there's something wrong with the engines (like you also suggested on my 27mpg average)... I would really like know how you drive and get 40+ with a/c on and on hilly roads.

 

I drive a manual, speed, and take it out of gear every opportunity there is to coast downhill, and use the excess momentum to take the car far uphill before putting into gear. There are sections of road the momentum of the car will allow me to be out of gear for a few miles without ever dipping below the speed limit. Not unlike how you can ride a bike on a pump track without ever spinning the pedals. If I didn't use the hills as I do, I'd probably be getting around 36-37.

I'm not the only one, rajahx is saying he's getting 35 first tank. That's what I got my first tank, MPG should go up as the engine and tranny wear in over the first few thousand miles and friction goes down.

I think OP's problem is a math error, and will resolve next tank. But anyone's car that suddenly drops 7-8 mpg when they haven't changed driving habits or routes needs to have the car checked out mechanically. That's simple common sense, decline in fuel economy is a warning sign.

 

You are aware that the injectors shut off if you are in gear, with zero gas pedal input, and going down hill right?

 

If you're shooting for economy, then leaving the car in gear is counter productive. It won't coast as far in gear as out, and it certainly won't gain as much momentum downhill with the engine acting as a brake.

 

right, but it also uses zero fuel during that time.

 

Which does zero for fuel economy if you have to put the car back in gear sooner on the uphill.

 

I filled up yesterday, drove home .9 miles and it said I got 19mpg, so today I did a 50 mile trip going without ac at the 25 mile mark it was 47mpg no a/c on return 25 miles with a/c it showed 43mpg. on total 50 mile trip, loss of 4 miles per gallon on entire trips so actually it would be 8 miles per gallon less just for the a/c.

 

so are you suggesting for us to drive like you? or else there's something wrong with the engines???

you do know that there is more other driving characteristics and driving habits aside from yours... yes?

not all drive likes a granny.

 

100 degrees, AC on all the time city driving here gets roughly 35-37mpgs.

 

No shit, sherlock. Some of us know how to drive fast and get good mileage too. Imagine that.

Sorry if you can't comprehend that OP posted about a sudden 7+ MPG drop. Mileage may vary 2-3 tank to tank but if it drops that drastically for no good reason, then time to check out the car.

Tire inflation, sticking parking brake, dragging brake shoe, stuck caliper piston, bad thermostat keeping engine in cold loop, do you want me to list the hundreds of mechanical reasons he could experience such a mpg drop that wont trip a code? Just because the CEL isn't lit doesn't mean everything is fine.

 

Been averaging 33 to 35 mpg usually running high rpm going up ramps when entering on the highway. Occassionally down shifting on steep inclines to maintain speed or pass. Going 900 miles lots of hills in PA, VA and NC average 33.4mpg seems reasonable since the the car is rated 33mpg highway.

 

His description of his typical driving sounds like a pizza delivery. I can easily see 19 mpg in that kind of driving. But to fall to that in just one tankful? If the wearther changed there like it did here the a/c loads would esily double. Yeah, I check the engine - AND CLUTCH FOR SLIPPAGE - to make sure the car is in good shape too;from his route his clutch might be slipping