T6 strange engine wobble

[kirkm5238]

Hi Guys have a t6 euro5 0n a 16 plate it’s got got 33k on it now when I start my van in winter starts first time straight away runs lovely no problem but in the warmer months if the out side temp is around 15 when I start from cold i Get a slight shake if I give it a little bit of throttle it goes away sometimes it doesn’t do for weeks I’ve had it do it twice like a slight miss fire no codes on it could a battery cause it it’s still got it’s original on gets all the filters changed around the 5k mark every year aswell thanks