Volcom86 Posted May 12, 2021 Report Share Posted May 12, 2021 I have an issues with cold starts that has always been there since day one after a tune was done. On my Flex tune it doesn't matter if I am running on Petrol or Ethanol it's the same for both scenarios. The issues is the AFR's will dip into the low 10's AFR on the gauge under .7 Lambda which is way to rich and stinks out the garage/surroundings badly. Then it slowly creeps up into the lower 13's AFR till it hits about 80 ECT where it will creep into 14.7 AFR What would be the ideal AFR Target for cold starts and how do I adjust this? Thank you for any feedback as it will be much appreciated. Quote Link to comment Share on other sites More sharing options...
Adamw Posted May 12, 2021 Report Share Posted May 12, 2021 There are a combination of factors. It looks like Post start enrichment is quite a bit of it, when that disables around the 50sec mark your lambda is back to about 0.85. So you can reduce that and its hold decay time quite a bit by the looks which will help. IAT fuel trim should normally be off for modelled mode, although it is not having a big effect in this case. Otherwise I would guess the charge temp approximation is a bit too heavily biased to ECT in the idle area. I would not recomend adjusting that at this stage as it will effect the whole tune. If you want to pull a bit more fuel out for cold start I would turn on a 4D fuel table, put ECT on the axis and remove a little that way. Volcom86 1 Quote Link to comment Share on other sites More sharing options...
Volcom86 Posted May 12, 2021 Author Report Share Posted May 12, 2021 Thanks @Adamw I will try it out and report back. Thank you for the feedback Quote Link to comment Share on other sites More sharing options...
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