2009 Honda Fit Sport
 

I recently purchased a 2009 Honda Fit Sport MT after my Focus literally went up in flames. I was pleasantly surprised that I was able to achieve 40.2 MPG on my first tank after the dealer's provided tank that gave me a bit of time to get used to the car.

I now have 6 tanks logged. The first one was still the best but I was fairly close with the others and currently have an average of 38.4, well above the 33 MPG EPA.

I've made no modifications to the car. But I figured I could still do a little better. Instead of just relying on the builtin MPG readouts, I recently connected a bluetooth OBD II reader and setup Torq on my phone. I think the main advantage with Torq is that it doesn't max out at 80MPG and I can actually see differences when I'm above 80.

I had read that there's typically a fuel cut off on engines when coasting in gear, so that's what I had been doing. But after watching the readouts on the torq app I noticed that if I coast in nuetral I get signifigantly improved MPG over coasting in gear. Something like 180 MPG vs 110 in gear. I wouldn't have been able to see that difference on the car's readout. The average MPG on both the torq app and on the car's readout have improved at least by a couple MPG since I started using the app.

I'll be very interested to see what my next tank's mpg is, but I'm almost certain it will beat my best. I'd love to see other Fit drivers input on coasting in gear vs coasting in nuetral.

Congrats on the Fit BlueFoot. The guys here seem to love them, and they do get pretty good mileage too.

My first tank was 37 and change, but it was in February. I'm coming up on 30k miles in mine and loving, loving, loving it.

Disregard the Feel Good Bar of Mileage, it's useless. Coasting at 60 mph gets me around 270 mpg. You can try bettering that with DFCO, but you aren't going to keep your speed up. Don't do it in gear unless you wanted to be on the brakes anyway.

Torque is really good, but you probably want to get a ScanGauge or UltraGauge to avoid having to mess around with your phone all the time- key off EOC was what really soured me with Torque.

I've considered the ScanGauge but got the other one mainly because of price. I may consider ScanGauge in the future if the Torque app becomes a pain in the butt.

Fat Charlie, does your MPG readout and ScanGauge MPG readout end up pretty close to the same as calculated tank to tank mpg? Mine seems to report quite high on both. I read somewhere that the 2009 Fit is 20% optimistic with it's MPG average and that there's possibly a reprogramming I could do at the dealer.

On my best tank, the MPG readout said 45.1 but when calculated by fillup it was 40.2. It currently reads 47.0. I'm hoping that's a good sign.

I actually have an UltraGauge, which at least at the time was the cheaper of the two. It paid for itself almost immediately and as for convenience, it's just another part of the car. I spent $7 on their "horizontal surface mount" and have it above the steering column offset to the left, blocking the part of the tach that is just wasted space anyway.

The OE gauge is the OE gauge, and it's pretty accurate for what it is- but the real advantage to one of the good ones is that you can calibrate them. At fill up time you can tell it how much gas you put in and how far you've driven. Then zero out the trip numbers and repeat at your next fill up. After a few tanks you'll be able to trust that the numbers are accurate and only verify them every several tanks. I also told the UG that I have a 10.1 gallon tank, giving myself a predictable reserve off of the calculated DTE. Just because you've been getting good mileage over the course of the tank doesn't mean conditions will be good during your last gallon, you know?

I leave the car's odometer showing trip miles and reset that at every fill up. Every few days I might cycle through the display to see the car's mpg calculation just to say "yeah, that's pretty close to the UG." This morning the UG was showing 54 mpg for the tank and the car showed 52.7. Disagreeing by one and a half mpg is a lot when you're near 20 mpg is a lot- but when you're more than twice as high then it's close enough to be happy with.

My limited experience with DFCO is that it varies quite a bit from car to car. For example, my 2001 Silverado 3500 6.0 gasser only actuates dfco if truck is going faster than 40 mph, and engine is above 1000 rpm. It also is slow to activate dfco; it seems to want to be sure that one is serious about decelerating to activate it. Sometimes touching the brake pedal will activate it and other times not. Another example: My 2005 Camry 4 cyl auto trans activates dfco whenever the car is decelerating. This occurs even when in cruise control. Whenever the cruise lifts off the accelerator the dfco is activated. I like it.

I guess my next question is, how do you know for absolute certain that the Fuel Cutoff has kicked in. I can watch the fuel flow/minute readout, but when coasting it's already so minimal it just shows zeros. Is there a different readout I need to be watching? I guess the fuel flow per hour would show zero as well?

How I "know" (actually "assume") it is in dfco is that my ScanGuage E gives mpg as 999.9 which is as close to infinity as it can get.

But your question raises a question in my mind which is that I don't actually KNOW that dfco has been activated. hmmm

I suspect that we would need to monitor the pulses to an injector and when there are no pulses or very few pulses, then we would be in dfco.?

Actually, if you monitor the primary O2 sensor on the scangauge, you'll know you are in DFCO when it reads a steady 0.000 or similar. That means no fuel is getting burned

I'll try monitoring the O2 sensor readout on my commute tomorrow. But it doesn't seem like my car has fuel cutoff. On the torque app my mpg will go up to 255 while coasting in nuetral. Coasting in gear it seems to max out around 120.

There is no question that an 09 Fit has DFCO. My 1998 Civic has it. And so did much older Hondas, I am told. Honda was somewhat early in applying this technology widely in its car, it seems. Suspect the torque app and the scangauge... they might have settings that need adjustment. My ultragauge had to be set to recognize dfco. If your engine is warm, in gear, and rpms are over 1100 you'll go into dfco within one to 3 seconds as soon as you take your foot off the throttle. Sometimes you can feel it, since the car will often shudder slightly when fuel gets cut.

I can't imagine the '09 Fit doesn't have DFCO either.

Do your self a favor & get an Ultragauge. You will NOT regret it.

Think engine braking, not DFCO. DFCO isn't a way to save gas, it's a way of sweetening the deal when you purposely induce drag.

So when exactly would DFCO be advantageous? In every case I can think of, coasting in neutral gives more advantage. I can see the theoretical advantage, but haven't been able to see any practical one.

When you have a need to slow down a bit more than coasting alone will get you. It happens a lot.

Then maybe the torque app isn't giving me good readouts. I've always seen more advantage coasting in nuetral and using the brakes rather than DFCO on the mpg readouts, or I'm not actually able to get it to do DFCO. But it seems like it should be pretty simple to do DFCO.

If you decide to want a UltraGauge shoot me a PM, I'm not using mine anymore.

Maybe torque isn't capable of reading when the engine is off? Idk.

Fat Charlie, I don't want to hijack this thread, but we could use a thread that describes how different manufacturer's/cars dfco's work. My experience is that they are not all the same.

I just filled up and got a new best tank of 42.48 mpg. The only difference was using the torque app vs my car's readout and more experience with my car. It hit triple digit temps here today, so I'll probably have to start using AC and drop the mpg a bit.

Might be worth checking if your FIT has a minimum RPM for DFCO.

My previous 2011 toyota wouldn't go into DFCO mode unless the engine was over 1400 RPM when it started (i.e. when I lifted off and the car momentum was turning the engine). It would then stay in DFCO to under 1400, 900 was the minimum - the idle speed.

If I lifted off under 1400 then the ECU would select the idle program and inject enough fuel to maintain that. As the engine was now in effect idling at (for example 1300 RPM) that used more fuel than just selecting neutral and coasting.

Also worth observing what happens at low speeds - e.g. some cars have "convenience" features such as raising idle RPMs at low speeds or reverse (especially on smaller engines) to try and prevent people stalling when moving round car parks.