2008 Daihatsu Hyjet Idle up problems-Piaggio porter-daihats

I have Piaggio porter with daihatsu engine 1.3 V 16V efi (from daihatsu hijet). The problem is because when I start the engine first time it works with non-stabile idles for first 10-15 seconds-after that it works normaly. TPS is changed (it wasn't work well), Vacum switch valve (VSV idle up) works when is jumped at 12V well and have correct values according to manual, inlet manifold is cleaned, vacum pipes are checked.I have 12 V (13, 3 aprox) on the connector for the VSV when the engine is running at idle speed. It happens only in the morning when I first time start the engine. After that when I start the engine again it works ok. There is no lossing of power or any other symptoms that I noticed except that - unstabile rpm at first start in the morning