(aside to MPGASAP - man... that little gal is so gonna whup some ninjoid arse!)

 

I have seen my mpg be off for two different reasons, first is like what SB is leading to in this statement is that if a refill is not complete for what ever reason your mpg wil be very close computer's and the next one with a full fill up will have a larger difference but will bring the average of the two back in sync. I have had this occur twice and factors were pump and time of day (weather) differences.

A second way I see a larger difference is based on my stye of driving. For most of one tank I was in a bad mood and was tending to drive more agressively and was harder on the gas pedal and the difference was almost 14%.

SN

 

I have a 09 5spd sport.
The gauge is rather consistent at 5mpg to high. I am still betting the highway mileage rating but the gauge sucks.

Do it right or don't do it at all!

 

https://www.fitfreak.net/forums/2nd-...tml#post778186

Download Fit MPG.pdf from Sendspace.com - send big files the easy way


YAY

 

The computation is based on injector pulse width, count and vehicle speed. Where do you get your (bad) info from?

 

So, is this to mean that if we all head to our dealers we can get this fixed now?

Odd thing- my gauge is actually consistantly very close to actual mpg's- like within a mile, to spot on. I'm considering leaving well enough alone. Weird.

 

If you do not experience the symptom this isn't a required update; the bulletin does say to check with real, manually calculated mileage data. I ran the update on my car before the bulletin came out; it was labeled with the program number (which is numbers and/or letters that mean nothing) and the non-descriptive label "Mid MPG Update". I thought "hey, maybe I'll get better mileage".... and it went DOWN. Then the bulletin came out about a week later. Oops lol. I'd still rather have correct worse (34.7mpg current) mileage than a higher incorrect number.

For those of you worried about a dealer running this without your knowledge, this would not come up as a recommended or required update, it is available to assist technicians in troubleshooting a customer complaint.

This is the most apropos use of this phrase ever "YOUR MILEAGE MAY VARY"

b

 

Finally, a fix for my ONLY (minor?) gripe about the 09 Fit!!!

 

jpg for easy reference. link to pdf on scribd.

This info is really appreciated!

 

Well I will try to remember to ask for upgrade at first service.

So 34 is bad? I get about 41 mpg Cdn or 34 US and I was happy. Maybe I shouldn't be?

I could improve my mileage if I drove the speed limit too but it is so nice to hustle the Fit. My weekly 120 mile trip I drive about 75 - 80 mph.

 

Honestly, it's just another stupid sensor, it's obviously going to be off within a certain amount. I refuse to believe that there are car's that are "dead on" all the time, especially pontiacs.

 

uh no it isn't. It's an integral part of the fuel injection system. The control unit has this information in order to meter fuel correctly. Displaying the rate of consumption is an easy task with today's electronics, but some geek got a constant wrong so the display is off by a constant amount.

Nothing on a modern car "is just another sensor." All data is polled and used to control the engine. The tach, speedometer, and mpg display are all "just displays" of what your car is doing. For Honda to stick a display front and center that had such a huge error is laughable (at least now they have a software update to fix it).

 

You GM haters would be surprised to know how dead-on some GM displays can be...

Finally, a fix for the one really nagging problem with the Fit!

 

I have had this feature on several cars before the Fit, they were always VERY close (within a tenth or two). It's not hard to calculate total fuel injected (pulse time*injector flow rate)/vehicle mileage. The FIT computer was off on my car by approx 10-15% depending on the trip type.

 

I have a 09 fit LX 5 speed manual here in canada - had it for 1.5 months with just over 2000kms.

I use the following manual calculation: fuel used x 100 divided by kms driven

Please correct me if i'm wrong

I reset the trip counter every fill up

The only items I can cycle are - total kms driven, trip A, oil life, avg kms / litre

My typical is about 6.3L / 100kms (at least thats what the computer says) but my last manual calculation was 6.8 in mostly city driving.

Does the dealer service bulletin apply to canadian 09 fits as well? Any canadians go to their dealer to bring this up?

thanks

 

If the computer says 6.3 and your calculations are 6.8 that's about a 7% inaccuracy (0.5/6.8=0.074) . My differences typically run around 13% as described in the bulletin (33 mpg actual, and 37.5 mpg displayed, 4.5/33=0.136). Your 7% is a greater inaccuracy than I'd expect with the fix but it may be within Honda's allowable margin of error. You'd need to check exact figures to be sure.

(Can we program ours to display L/100km instead of MPG? I wonder if it would have the same degree of accuracy? Did I just type this out loud?)

If you're curious, email the bulletin to a honda service adviser up yonder and see what they say. It was just released here last week so they may not have it yet even if it is a problem. Here's the link again:
Fit MPG

 

i called my dealer service dept.

it took him 10 minutes to find the bulletin. he didn't know of the problem or the bulletin.

he told i'd have to show him my documented mileage vs. what the monitor said. no problem.

and he said the repair will take 60 to 90 minutes.

why should a software fix take so long?

 

After running the MPG update I filled up this morning, was getting low (put 10.582 gallons into a 10.6 gallon tank)... my computer showed 34.8, my manual calculation showed 34.889. My prior tank showed 36.9, my actual was about 33.

Thats close enough to shave...

b

 

The SB quotes 0.3 hours. He's allowing time for the mechanic to scratch (insert body part here).

 

I just got off the phone with a service advisor at Carter Honda in Vancouver BC, he said they don't have an update for this yet.