Torque app accuracy?
 

i recently got a elm 327 adapter and hooked it up to my 4dr civic with auto trans along with a Torque app on my android phone.

It's showing about 45 mpg at steady 50 mph and i averaged 52 mpg on some recent trips with a warmed up engine. This seems too high for me ( i know the next fillup will tell me the truth but that will be in about a week) because i was getting about 40mpg with my other civic 5speed with lots of EOC. i never got to test the app with my old civic so i can't compaire them.

I heard about this on the Camaro forums. And as far as horsepower goes, I heard it was inaccurate by 5-7%. So it gives more of an in-the-ballpark idea. Fuel economy may or may not be in the same boat.

the way these programs calculate fuel consumption is based on reading sensors and calculating around a stoich mixture. the only truly accurate way to measure fuel consumption is to measure the injector pulse, and know exactly what injectors you have. but, manufacturers are not too keen on letting the general public dig into their computer controls to get the raw data.

i find the torque app measures slightly lower efficiency for my car. if it says 35 mpg i actually get 37 mpg. there is a way to callibrate it in the vehicle type menu. i use torque daily. One problem i have with the program is the logging feature. I downloaded a log and opened it in excel and it logs actual codes not values. it is unreadable to me.

Go into settings, then adaptor settings, make sure the Enhanced MPG calculation option is checked. This helped on my Kia. This app is not perfect, but it is a very cheap way to clear codes and see some of whats going on with a car. I dont regret my purchase.

Make sure you've got the paid version. First, Ian deserves his $5 (or whatever it is now) for putting that together and second, the free version doesn't get so much of his development time. Unfortunately things like mpg at the accuracy we need aren't really high on his List of Things To Do, but with the free version you'llbe getting his second-best.

I'm sure the longer its out, the better it will get.

I'm considering getting a mini tablet and putting it in my dash so i can use it as a stereo/ engine code reader, and a way to read my fuel economy. so for now i'll just sit on the sidelines and see how it goes.

so today i filled up and i was suprised that i averaged 34mpg (without any major hypermiling) the first tank with this car because i thought the automatic trans would really hurt gas mileage. So i guess the torque app is pretty acurate, i will never know for sure because i only turn it on once in a while because it's hard to get it started when i'm in a hurry.

-I'm taking a long trip and will be measuring the accuracy of this app.
-One thing that I did for the MPG instant reading is set the limit to I believe 115mpg (which is a little beyond what the reading goes to while coasting), because sometimes it jumps to the max (255mpg), and I think that this skews the average MPG reading.
-I will be comparing the fuel used figure to the amount of fuel that it takes to fill the tank up again, and will also be comparing the trip distance figure to that of the car's computer. Then using all of this data to see how accurate the MPG reading is to the individual readings of the app, and the actual MPG.
-As for the accuracy of the app, as detailed in the Torque forum, during some of the update intervals, one user noted that no fuel was logged as being used, so this would increase the recorded MPG usage, and decrease the recorded fuel usage.

With apps like these, you're really limited by the fact that they have to run on a phone and share processor and port time with other phone apps and the OS. I tried running a few for track work and the dog slow GPS update time made it an unreliable way of getting data compared to a dedicated GPS device.

Good for ballpark figures, though.

Well, it was sort of a bust. It seemed to give an accurate instant MPG reading, but the average MPG just kept on rising, and the fuel used reading stayed the same at one point. The other readings are valuable, mainly the vacuum gauge. I just turned it off after a while, because at freeway speeds it's really just keeping your speed down that results in good milage, at least the with auto transmission that I have.

Yes consider getting the purchased version. I would notice with the free version, that at idle or at stops, MPG stayed the same and wasn't deducted from the average MPG reading. But with the purchased version it would calculate the fuel consumed at idle, which would be more realistic as fuel is still used at a complete stop.

But I DO have Torque Pro, and this wasn't at a stop, this was at steady highway speed.
I also have "enhanced MPG calculation" turned on, but will try it with this off, because I read that this can actually skew the reading sometimes.

Go to the Torque forum and ask about it. A year ago when I was there, Ian was quite responsive and always tweaking the app.

I just got my OBDII adapter today and bought the full version of Torque. The gauges are super super nifty, but I don't know if they're accurate. There do seem to be manual correction "multipliers" for just about everything though, which is good.

However, my question would be, why does it matter? Fuel efficiency is not absolute, it's relative. As long as the app can tell you the correct lambda, load, and instantaneous fuel consumption (approximately), who cares about the actual mpg reading? I have my "main screen" set for fuel economy driving, with a bunch of less important indicators in "tiny" size sitting in the corner, and big displays for load, lambda, mpg. Drive so that lambda doesn't dip too far below 1 but load is high whenever possible, watch the mpg gauge in steady state cruise to determine the best course of action.

What is Lambda?

Oxygen equivalence ratio (I think that's the correct chemistry term for it).

<1 is rich, >1 is lean.

By the way, today I told a passenger to watch my phone for me and apparently it wasn't giving me measured lambda readings! I also looked at the commanded AFR and it just said 0.00:1 :(

I hope it's not because my adapter was 11 dollars and doesn't read as much stuff as it should...

Also apparently my %load maxes out at 75%, so I wonder if my air filter is really clogged or something.

seems there is a format that makes it get closer to the real value

If your trip or long term MPG avgs are off, tweak the multiplier under settings in 1/10ths and 1/100ths. Its a trial and error game for a few refills to get as accurate as you want.

My Taurus is pretty spot on for MPG, my Town and Country was off horrendously by nearly 10 MPG. the van is rated for 26 MPG @ Hwy. Torque Pro was initially showing 16 at best... Trial and error several adjustments from baseline of 1.0 trim, my 3.3L is now fairly close to accurate with an adj of 1.48 trim running roughly 24 MPG winter blend at 55 MPH.

btw, my ELM327 device is the OBDLink MX for reference cause Chrysler and Ford have their own special something or other that the cheaper devices could not read all codes or so the many pages I read said...... sigh

got another format in this blog
How to get MPG value/number with elm327? | OBDII365.com Official Blog