hi, when i start up my car in the morning or when the engine hasnt been started for like 3-4 hours, it starts crap, it will fire immedietly and for the first 20 seconds its fine but after that, the rpm goes up and then down and the AFR will go lean 17-18+ and the whole car shakes violiently, but after 2 mins when the car is warm it idle fine and drives fine...

why is my car doing that on cold starts only?

i will upload a video afterwards...