Stuttering and loss of performance

Hello, I’ve had a Suzuki Swift 1.3 with 68hp since Nov. ́06 and have the following problem. As soon as it’s cold outside, and of course the engine is doing so, Karre is bad at speeding you up and barely has any power.It goes so long until the engine is warm.He also has strong starting problems when starting when it’s cold, but battery is new and one of the Baleo, so it’s a little bigger. and already at 2500 – 3000 rpm switch. Does anyone have a good idea what that can be??? Thank you already!!! Greeting and show!!!