Flex Fuel Engines

[fernold2k]

Hi everybody,

I'm newer on this subject and I'm trying to fix my software to work with a Flex Fuel car. This kind of car works with any mix of gasoline and ethanol fuel.

I want to know what is the most accurate mode of measurementof fuel consume.

MAF - My car doesnt have this sensor.
MAP
Injector Sensor
Engineload Sensor
or
Builtin consumption sensor

[cail]

Hi fernold, what vehicle model do you have?

Basically you only left with MAP option, you'll have to tune up VE and AFR values.

[fernold2k]

I have a Pajero TR4. Here in Brazil we use engines that supports any mix of gasoline and ethanol in any proportion. So this variables are not fix, they change for each proportion of fuel.

Take a look http://en.wikipedia.org/wiki/Flex_fuel#Brazil

Thanks

[cail]

Fernold,

Since you don't have MAF working - MAP is your only choice. Setup engine displacement correctly.

Normally ECU adapts to the current fuel mixture and indicates this with LTFT parameter, or with Lambda parameter. Enabling adaptation to these values in vehicle settings will make hobdrive to calculate current air/fuel aspect ratio correctly.

Please make some observation to understand which of these two (LTFT or Lambda) is in a best way reflects change of AFR.

I've heard it is LTFT on some Toyotas, but for your Pajero it may be Lambda sensor.

[fernold2k]

I'll try this. Thank you very much.