Hello, i have a 2002 Toyota celica GT and i recently changed the sparks plugs and changed the oil but now i recently noticed that my car has been hesitating and bucking when i accelerate. But my check engine light and service light is not on either. ,My car would hesitate and buckle for the first 5-10mins of me driving it then it would go back to normal and no hesitations. Please any help would be appreciated Thank you in advance