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I have a few random questions I was wondering if someone can shed some light on.

Am I correct in saying a Modelled Fuel Set Up is an open loop configuration? For example, the ECU will work towards an AFR target based on parameters defined by the VE and fuelling in the fuel table, but will not make adjustments based on changes in variables such as IAT?

I'm also not quite sure how CLL would be used in the tune. Is it mainly for cruising or is it also used to help track a lambda target on power runs?

I've seen how closed loop set ups help track boost targets using the PID system, but lack context in relation to fuelling.

Modelled mode can be closed and open loop. Just as the injection time based model. If using a wideband O2 signal, CL can target above and below Lambda1, and Lambda1 dithering operation to make a catalytic converter work efficiently.

IAT and other correction factors are being taken into acccount if you choose so on both systems.

Modelled mode will take fuel pressure changes into account on some systems, such overlay table can also be created in timebased models.

CL is used to correct minor imperfections in the fuelling table. Some choose to go open loop beyond a certain boost load or rpm level, others keep closed loop in all areas, although richer than Lambda1.

Long term closed loop correction tables can help to finest tune fuelling the main table over a longer period of time.

Thanks Dom, that clears up the CL in relation to fuelling, however, I have more questions regarding the different modes.

Do you know where I can find more information regarding the differences between "Modelled Fuel" and "Traditional" mode? I'd like to know the differences between the two.

Basically, with a time based model, we will need to calibrate more compensation tables / factors, as opposed to the VE (Modelled Model).

A modelled mode is very useful when, ie. hardware changes are made. For example, a different set of fuel injectors, or different fuel pressure level. In such a circumstance the Modelled Mode will automatically re-calculate, and apply, needed corrections to the calibration.

Doh! I didn't see the extra courses specific to each ECU under the certification section.

Thanks for that Dom, that's a great help. :)

Glad to be of help.

Best regards


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