Hi, I have a 1987 Civic 4-door GL 1500cc Carbureted car with 50 state emissions and little over 92k miles. I had just rebuilt the carb, with the help of a friend who's a car professional, because it was very loud and sputtered so much that it was undriveable. I had to replace 4 month old Bosch +4 spark plugs because they were black. After we rebuilt the carb, the car was a little less noisy, and didn't sputter that much. As it warms up when it first starts it sputters more and I can also hear a sucking noise, sounding like the car is forcing in a lot of air. We also tried to solve the problem by leaning the mixture on the carburetor (as far as it will go). It seemed to help some by making it less noisy and reduce the sputtering a little bit as much so that it almost sounds like a "normal" honda. Also, the fan began to spin occasionally, which I had seldom seen it do. When I just put it into gear, it makes some weird decelerating- like noises and when I drive it, it sounds a little more normal, but the combustion still sounds bad (perhaps "dirty") and it hesitates on acceleration. My family has owned, up to present-day, 4 late-model honda cars (1 1990 civic and three 89-90 accords all fuel-injected) with lots of mileage on them and I have never experienced such problems. I am afraid its situation will escalate to what it was before I rebuilt the carb. When I first bought it 5 months ago it was sounding normal and seemed like a great buy. Have driven it gracefully for only 2k miles. My friend thinks that the carb's bushing might be leaking and I may need to replace the whole carb. Here is a list of the things I have recently replaced for it: spark plugs & wires, both fuel filters, fuel pump, cap and rotor, all belts, and alternator. I'd appreciate any advice, thanks.