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This may be a useful feature to assist with cold start tuning:

1. Add a field specifying the target idle rpm during warmup;
2. Add a field specifying the upper temperature limit for cold start compensation;
3. Enable a feature that adjusts the fuelling in order to meet the target idle rpm during warmup (i.e. as long as the throttle position is 0% and water temperature is less than the upper temperature limit;)
4. Populate the turns/temperature fuel compensation table with the percentage values applied in order to meet the idle rpm target;
5. Utilise the populated percentage compensation values to control fuelling above 0% throttle.

This would add a considerable degree of automation to the notoriously tricky area of cold start tuning.

Thanks, Richard

Idle speed does have a target for water temperature.

There are adjustments for enrichment based on temperature.

There is closed loop lambda...but of course this requires the lambda sensor to be operative.

You're almost wanting to use closed loop features...to do the work of a tuner....without actually doing the work needed in order to make those closed loop features work in the first place ?

Cold start is only tricky if you make it so.

Yeah, not overly difficult as it stands - you need to tune the engine first obviously, then the next morning check the coolant enrichment as it warms up and adjust as it runs through each point. Generally you get it pretty acceptable in a single warmup. You do need to understand how everything works though so you aren't faffing about changing things that you shouldn't be.

Thanks guys.

I'm well aware that the process can be done manually, but also (coming from the software world) aware that a closed loop type of feature can automate what can be a hit and miss process. No lambda would be required. Obviously a tuner or a decent cold start map would be required at the start, but many people would find it impractrical to use a tuner to get the cold start map properly set up.

Not really sure what you are looking for that isnt there already? Cold start isn't that difficult if you have a knobs box, as you can rapidly see what sort of enrichment the engine wants by making big sweeping changes.

rjwooll wrote:Thanks guys.

I'm well aware that the process can be done manually, but also (coming from the software world) aware that a closed loop type of feature can automate what can be a hit and miss process. No lambda would be required. Obviously a tuner or a decent cold start map would be required at the start, but many people would find it impractrical to use a tuner to get the cold start map properly set up.

You cannot even attempt to finalise cold start until hot running is sorted. There may be a little bit of a paradox in there, but only a little.

And closed loop can only operate within the parameters the tuner sets up for it....

And there is a sort of closed loop system at play. Try to start....tuner makes adjustment, it starts. Repeat process until good...end of closed loop LOL