hard starting, rough idle
hello all i am new to the forum and need some help. i just bought a 1998 buick century with 92,xxx miles. when i try to start it i have to push on the gas to get it going and it drives great. but when i get to work and am idling it gets really rough and seems like it wants to cut off. i have replaced the air filter, fuel filter, air charge temperature sensor and the idle air control valve. i have also thouroghly cleaned the throttle body. im running out of ideas and any help is appreciated. thank you.