Thursday, December 19, 2013

Drivin' in the rain

Rain has an adverse effect of mileage.
Here's a trip at 3 degrees with clear weather: 20.43 km/l (4.89 l/100km)

And the same trip with 2 degrees and light rain: 19.01 km/l (5.26 l/100km)

Wednesday, December 18, 2013

Increasing engine temperature for fun and gain

Following my previous investigation about temperature effect on mileage, I tried covering the front grid to help the engine gain and maintain temperature.
The first tests on my daily commute trip seems encouraging:

Trip with no radiator cover: 18.46 km/l (5.42 l/100km)

Trip with radiator cover: 20.43 km/l (4.89 l/100km)
Net gain: 0,53 l/100km
Given that with a full tank of gasoline I drive for 700 km, that leads to rougly 3.7 litres of gasoline saved, or 6 Euros at the actual fuel price.
The radiator cover cost me 5 Euros, so I''ll begin saving money at the first refuel.

Sunday, December 15, 2013

Ambient Temperature effect on Mileage

Temperature are falling quickly these days.
We've fallen from 9 degrees to 2 degrees recently.
Here is a mileage chart of my daily trip at 9 degrees:
Mileage was 21.29 km/l (4.7 l/100km).
Here is the same trip but with 2 degrees ambient temperature:
 Mileage was 18.46 km/l (5.4 l/100km).

Lower temperature affects engine temperature: lower values lead to lower efficency and higher consumption.
The HV battery can provide less current, so EV mode can't be used as much as in summer.
Even low speed starts cause the engine to turn on.
Car heating worsens the situation even more, causing the engine to run just to produce hot air.
This can be seen in the ICE statistics:
At 9 degrees, ICE is off 40.1% of the time
At 2 degrees, ICE is off only 36.9% of the time.

By comparison, here is the same trip with hotter weather in November (I wasn't tracking temperature at the time):

Mileage was off the scale at 25.4 km/l (3.9 l/100km), but I've scored even better values in the summer.
ICE was off 60% of the time.

Monday, November 25, 2013

Introduction to Hybrid

Driving an hybrid car seems to scare some people.
Here is a "for dummies"-style introduction which I gave a little contribution in writing:

Service invoked too many times

Service invoked too many times in a short time: spreadsheets. Try Utilities.sleep(1000) between calls.

If you are getting this error while running AnalyzeTorqueLogs or Resume, try running them from within the editor, by selecting "Tool / Script editor..." and then "Run" from there.

V25 available

  • corrected one error that prevented execution if the sweet spot PIDs were unavailable

Friday, November 22, 2013

V24 released

  • S1 Chart
  • Added Coolant Temperature to SOC Chart
  • Added Coolant Temperature and Altitude to Mileage Chart
  • Charts now reports Altitude delta rather than absolute, to avoid scaling issue in mountain trips

Thursday, November 21, 2013

Some more gauges for Yaris dashboard

No chance of getting them on the real dashboard

Changing scale from time to distance

Most charts have time on the X axis.
Here's how to change to distance.
Note: you must have "Trip Distance" PID in the log for this to work.

Example: changing from time to distance in the Speed / Altitude chart.

Go to the Speed / Altitude chart

Click anywhere into the chart to cause the edit arrow to appear:

Click on the arrow and then select "Advanced edit..."

In the chart editor window select "Start"

Then click on the "Get data range" grid

Select the first data row

Click on the "Data" sheet

Click on the column header of the "Trip Distance" PID: the whole column will change color and the data box will change with the column letter.

Click Ok and then Update on the chart editor window.
Chart will be updated with km on the X axis.

Extending charts

Builtin charts can be extended easily.
Example: adding Coolant Temperature to Speed / Altitude chart.

Go to the Speed / Altitude chart

Click anywhere into the chart to cause the edit arrow to appear:

Click on the arrow and then select "Advanced edit..."

In the chart editor window select "Start"

Then click on the "Get data range" grid

Select "Add another range"

Another box will appear

Click on the "Data" sheet

Click on the column header you want to add: the whole column will change color and the data box will fill up with the column letter.

Click Ok and then Update on the chart editor window.
Chart will be updated with the selected column

Wednesday, November 20, 2013

V23 released


  • better handling of resume on "Execution time exceeded" error
  • sweet stop analysis (low RPMs with high mileage)
  • two new PIDs required for sweet spot: "Timing Advance", "Engine Coolant temperature".

Thursday, November 14, 2013


While investigating on ECO mode, I was curious to check if that mode affects fuel consumption.
I've driven the same track in Normal and in ECO mode:
I've found no differences.
Let's see Accelerator Pedal:
Wider range in ECO.

V22 released


  • % of braking while moving
  • added Resume for "Execution time exceeded" error

Wednesday, November 13, 2013

Dangerous docking

Mileage + Speed = Night sailing

V21 released


  • Glide evaluation now considers accelerator pressed
  • Pulse evaluation rewritten

  • Corrected error in trip lenght
  • Mileage chart has now a cap at 50 km/l to avoid overscaling (cap is customizable, see Tools/Script editor)

Monday, November 11, 2013

V20 released


  • better diagnostics in log error messages
  • pulse detection now check if accelerator is pressed
  • longest pulse is now reported in analysis
  • glide is considered valid only if speed > 10 (to avoid crawling)
  • glide chart is drawn even if pulse is not available

Sunday, November 10, 2013

V19 released


  • Hybrid chart now more readable
  • Added Pulse evaluation, with new chart and map
  • Corrected error on Glide % in Analysis sheet

Hybrid Art

Pick up a trip log.
Classify car states.
Assign a value to each state so that longer state have a lower value.
Draw a graph:

A little Manhattan skyline, a little Tron, a little Mondrian...

Saturday, November 9, 2013

V18 released


  • Automatic removal of duplicate header lines (but check log sheet and investigate why they're present)
  • RPM / Fuel Flow chart now uses corrected fuel flow
  • Count of EV Excess usage added to Analysis sheet
  • Fuel Comparison chart is drawn only with original fuel usage if fuel can't be corrected by missing PID (check log sheet)
  • Uncorrected fuel economy added to Analysis sheet

Charts explained

The Results page has been updated with some more info about charts meaning.

Friday, November 8, 2013

V17 released


  • Torque fuel flow PID seems to be affected by some errors on hybrid cars: it accounts for some fuel usage even when the engine is off: this release include some heuristics to correct fuel usage.
  • Added a comparison chart between original fuel usage from Torque and the corrected one

  • Rewritten coasting and ICE off detection for better precision. Note that this now requires "Actual Engine Torque" PID.
  • Added chart of car states (EV, ICE Off, ICE spinning, Braking, Coasting)

  • Km/l is now capped at 99 to avoid scale issues on chart.

Wednesday, November 6, 2013

Torque Fuel Used

It seems that the "Fuel Used" PID is affected by some errors: sometimes it reports a little consumption even with RPM = 0.
I'm currently experimenting with some heuristics of fuel correction for the next version.
Here is a comparison chart between original Fuel Used and the corrected one:

Auris RPM at highway speed

Here is a long highway trip at highway crusing speed.
Note that after 3500 RPM the steepness change.

Sunday, November 3, 2013

S1 comparison

Here is the S1 phase from Yaris and Auris.
First a couple of Yaris:

All shows the same behavior: SOC gains more than 5% (7,05, 5,88, 12,1 respectively), with max currents between 34 and 29A.

The Auris shows a different pattern:

SOC gain is very little (2.7%, 5.09%, 1.5%).
Note the longer S1 of the second car. It doesn't seem to stop even at 40 degrees.
Higher current generation begins in the later phase and even then, absolute current values are lower that those from the Yaris.
The last chart lacks Current and Temperature, but it shows very little SOC gain as the others.

Saturday, November 2, 2013

V16 released


  • SOC Chart

  • PID names are now more flexible (it should avoid some errors when importing csv files)

Friday, November 1, 2013

V15 released


  • Distance and KPL added to analysis sheet
  • Check for AP min value (should catch some import/capture errors)
  • Added Hybrid chart for those who don't want to use GPS
  • Increased chart size
  • Coasting and and ICE Off now consider fuel flow and are not fooled by Cruise Control (Fuel Flow PID is mandatory)
  • Better EV mode detection

RPM and Speed from a Prius 3 MY2010

CC usage results in an clear horizontal line

Thursday, October 31, 2013

V14 released

As 13 is an unlucky number, here is version 14:


  • SOC naming error corrected
  • Altitude naming error corrected
  • Added more grid lines in charts

  • ICE Off and EV % were off in the last version
  • Added EV to the Hybrid Map
  • Fix for missing time on charts
  • Car detection is more accurate
  • Added EV chart to use when GPS is missing.
  • Prius2 is now working again (need some work on Accelerator Pedal though)