I bought my Mazda a few years ago and it always runned smoothly (5-speed manual, 200 000 km). For the last few weeks, I've been experiencing hesitation problems. When the car is warm, the engine sometimes hesitates slightly when I give little or normal steady gas. There is no hesitation when I punch down the gas pedal. It seems that the problem happens around 2500 RPM but I'm not sure cause I don't have a RPM-meter. The car is fine when cold.Could anyone help me find out what's wrong?