Instant fuel consumption

[lcampana69]

Hi,
I do not understand the fuel consumption algorithm used for the diesel engine. What is the meaning and where can I find the "RPM curve for EngineLoad" for a specific vehicle? (Fuel calculation based in the engine load sensor)

[cail]

Hobdrive's user's manual have some information on how it is calculated.

There is no way to get a definite curve for your engine. The only way unfortunately is to experiment and review the data.
As a simple way, you may want to tuneup not RPM Curve, but EL coefficient. Often this is quite enough.

[lcampana69]

Thanks Cail,
As you mention, could you tell me a practical way to tuneup my own car? (The car should be in movement or it can be stopped with the engine run)

[cail]

Put full tank and run with hobdrive always on all the tank.
After full refill you'll know how much fuel you've spent, and what distance on tank was (use builtin odometer for this).

Compare these numbers with hobdrive, see difference in MPG numbers. If any, adjust EL coefficient appropriately (it is "1" by default).

[zakarevicius]

I used EL coefficient 3.5 for my Mazda 5 (105 Kw diesel) and I put full tank and run with hobdrive always on all the tank. Hobd shows 7.3 L/100 km, and I get 7.1 L/100 km. It's very good I think. But usualy my speed is until 90 km/h (about 1500 rpm). But when speed increases under 90 km/h and more HOBD show about 8 l/h and more. I think it's too much. May be RPM Curve could help?

I find that you suggest for ryslan it?

viewtopic.php?f=9&t=343

May be you can help and in my case?

[cail]

In regular trips, do you come over 1500prm often? What is a red rpm zone on your engine?

I would not recommend changing this, because we don't have external source to compare data.

With Ryslan he had a possibility to use his friend's vehicle, identical, but with builtin trip computer - so we could compare and correct coefficients.

You may collect such an external data - f.e. drive full tank on a highway with > 90km/h and see if hobdrive is correct. But this is not always possible of course.

[Mariia]

After full refill you'll know how much fuel you've spent, and what distance on tank was (use builtin odometer for this).