my 91 mazda has had a really bad rought idle on it for about 6 months. i just recently got it and over the last 6 months it has gotten worse. i am new to the mazde line, and i was wondering what could cause this problem, other than the spark plugs and wires. when i am driving the engine performs good, but when it gets to idle it just seems like it wants to die. is there a idle control motor that might be going out? i got a 4-cylinder in it, and it has 160,000 miles on it.