A while back I sent my '09 Fit (Auto) to the dealer after receiving a recall notice in the mail. (Possible Spring Assembly Failure recall.) I didn't think much of it until I started driving and saw my MPG take a serious nose drive. (I've been keeping track of my miles-per-tank almost obsessively since I bought this car in late 2009, so I'm pretty familiar with it's "mileage habits".)

Before I went to the dealer I was getting a solid 300 miles per 9-10 gallons.

After the dealer I'm getting about 260 per 9-10 gallons.

I haven't been driving differently or gone to places I don't normally go. Last year, from winter through summer, I got a solid 300 miles, even with mixed city/highway. Now straight highway driving doesn't seem to be improving my mileage. I'm stuck at about 260-270..

Is it possible that by fixing something from the recall they messed something else up? I'm somewhat mystified as to what they could have done to drop my MPG so badly. I suppose I ought to contact my dealership and see if they can fix it, right? What do you guys think?

 

My recall was done at a dealer about 500 miles from home. I was out of town and have family that works with dealer. If anything my MPG MAY have gotten a tiny bit better. It may take a few more tanks to tell.....

 

i assume if the valve adjustment wasn't done well during the recall (and there are plenty of complaints on the matter) your MPG could decline.

my MPG have gone up since the recall, but i can't prove it's because of the valve adjustment.

 

I just took a trip across the western USA (after the recall was performed) and noticed a bit better mileage then a similar trip last year. Best mileage was over 44 mpg going through Utah with speeds of from 70-80 mph.

 

Thanks. I think I might call my dealership again about this. I've given this enough time to see if there'd be any improvement. It's been over 2 months now and I'm getting a solid 260 miles per 9 gallons were as before I was getting at least 300 miles.

I'm jealous of everyone's MPG that went UP.

 

I'm about to get a real good test....driving half way across country....I'm going to keep good track and see what happens...but looks good in my local driving.

 

I would check the tire pressure and oil level, then try premium. The low mpg your car is getting sounds like knock retard. http://www.goldeagle.com/UserFiles/f...dated_Logo.pdf

 

SilverBullet, Honestly, I'd be really surprised if that were the problem. I'll check the tire pressure sometime this weekend. But the oil should be fine, unless the Dealership changed it on me without saying so. I get it changed every year, before our big holiday trips (Texas to MS to FL), it's always at the same place and the same oil. Never had an issue with it before.

 

First thing I would do is get a more accurate number on the MPG. Calculate at the pump over three fill-ups and you'll have a good average. You might be doing this, but miles per tank really isn't a good reference.

What are you seeing on the OBC for average/instant MPG?

My FIT gave a slow improvement in MPG till around 10K miles. I've found it's primarily in your driving profile and the fuel being delivered to the pump. I've seen a seasonal change, so air temps and winter fuel blends have an effect. Weekly fuel deliveries can vary as well it seems.

Also, I have always gotten better local MPG than highway. Right now I'm seeing an average of 38 local [rural/suburban]. It's been down to 36 highway. Put me in a city environment and it's down to sub 35 if I hang around too long.

Regarding the recall and it's effects on MPG - I seriously doubt it. If you do go to dealer post back what they think.

K_C_

 

Pretty good manual. It may have some bias as it's paid for by ethanol producers, but I don't see any.

Here's an excerpt from page 4:

 

Driving an 09 with 26K miles. I notice that where last year I was averaging 32mpg, this year I average 34.5. Same gas stations. Same route. Same driver. So there may be something to some Fits increasing MPG as they break in more. (Maybe the diameter of the tires is less, enough that it thinks it's going farther.)

You've gone from 30MPG to 26MPG, a drop of 13%. Uh, you didn't by chance have the ECU flashed while you were at the dealer? The factory data tables consistently had displayed MPG 10-15% higher than actual (measured at pump). Of course if you're going by manual calculations this has no impact.

If you've adjusted for seasonal changes due to using the A/C etc, I'd look for some mechanical issue. Alignment is a possibility. Poorly adjusted valves is another, but I'd think you'd notice other performance issues if this were the case.

Any other car you'd never notice a seasonal 10% difference. But probably we're all sensitive to it or we wouldn't have bought the things. That and the in-your-face mpg display makes it easy to obsess. I'd be asking the dealer to look at it too.

 

The fit is extremely sensitive to valve lash due to its higher compression. I had an immediate 4-5 mpg gain just from moving from the tighter end of the service spec to the looser end.

 

I post that one again because it shows a few things and if you look past the bias its very educational. The main point is the compression to octane chart and that they don't know that all cars made after '96 has a knock sensor the biggest reason that the car can run on regular.


I thought you got better mpg than that. Its not bad but I averaged 36 in my 08 Fit with 3 winters and 2 summers in the Chicago area driving the same route every day.

My point is try premium for a few tanks, the difference is the cost of a cheap fuel injection cleaner.

 

Who doesn't know?

From the manual you linked (and I excerpted above):

 

The authors of that link. Compression ratios where 9 to 1 or lower when the first manual was written and they have not updated it. 1996 OBDII came out and that required for a smart ecu but they used narrow band o2 with a 16 bit processor. 2000 They started to come out with a semi wide band o2 with a 32 bit processor. The Fits have a CAN controller which is one that the Volvo's first used. I am now waiting on the 64 bit processor.

I know there is a lot of miss printed info but its easy to pick out. Regular Gasoline can also be considered pump gas (reg,midgrade,premium). They also sell E85 and Racing fuel and diesel which is different.


I have shown enough info that shows its about MBT and how knock retard brings down mpg by adding more fuel to cool the burn.

 

I'm at my highest MPG on the vehicle ever. My last 5 tanks have been:
44.3mpg
41.7mpg
43.4mpg
42.6mpg
41.8mpg

For an average of 42.6mpg. This is all on Shell 87 octane. My average speed to/from work (including construction & stop signs/25mph towns) is 47mph based upon the GPS and one round trip however the tanks above also include trips into the "city" of rutland VT ususally hitting about 15-20 stoplights coming and going. My alst car told me I had an average of 40mph at most every fill up so I'm guessing that hasn't changed.

Had my recall done a few weeks prior to receiving my recall letter.

~SB

 

Way to obfuscate, SB. Are you in Illinois politics? Sorry, that was mean...


Uh no, you haven't shown how it brings down MPG in real life. Still waiting for that.

 

Damnit! I keep confusing people when they write SB. SilverBullet, SpecBoy AHHHHHHHH!!!!!!!

oh yeah... car was reading 43mpg on the 'puter. have about 300 miles on the trip odo.

~SB

 

Check the intake going into the air filter housing. Highly unlikely but I had a shop rag left in the intake of a Ford many years ago. Not mine. Dealer said "no way". I had a friend who put a modified intake tube system on a Element and managed to suck up a bread wrapper/bag. He was dirving and saw it dissapear into the front of his car. When he stopped for gas he couldn't find it and just out of curiosity looked into the intake tube. There was the bread wrapper.

 

phasfit, Please don't laugh... but where IS the intake for the air filter? If you can link to a picture or something that would really be best. ^^;;

I'm also well past the 20K mark. I go from North Texas to the middle of Florida at least once a year. Which is why I have a very very good idea what my standard highway and mixed mileage should be.

I guess it could be the heat. Admittedly I got the car checked out at the beginning of spring. Shortly there after we went into severe drought conditions for our area. We've been constantly breaking records with our high temps (105-109), we get heat warnings at least once a week. I've had our AC set to 2 at minimum, because the Fit's AC is not really that strong. (I love my Fit but it does take a while to cool down!)

I assumed it was the dealership because it was immediately after that, that our MPG dropped. My husband was the first to notice, since we took a Dallas trip shortly after. We had to fill up twice instead of the usual one time and he said it didn't seem as "peppy" on the highway (a very long windy, slightly hilly, stretch of road).

I didn't notice anything different though. And I'm usually the one who DOES notice. (as I drive the car more than he does.) Which is why I didn't mention it to begin with.





They didn't reset the MPG "automatic" calculator thing. It's still off by 2. Even then, it's still showing a drop in MPG. Haven't gotten over 30 (which is actually 28) since I got the car back.

I like calculating it manually, just for fun. So I know I never got lower than 300 miles per fill up, unless I was stuck doing stop-and-go traffic through the whole tank. Even then it would only drop to about 290. :-/