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I have a 1990 civic hatchback with a 4 speed. When it sits around for a few hours, it's really hard to start. I have to pump the gas a lot to finally get it to start, and then it idles REALLY low and sounds a lot like a lawnmower. Some light colored/greyish smoke comes from the tail pipe. If I take my foot off the gas, the rpms drop really low, and I'm not sure if it would eventually die, because I always put my foot back on the gas because I don't want to have to try to get it started again. I drove it around the block like this, with some mild revving to make sure it doesn't die, and eventually, the car returns to normal, and idles fine, save for some episodes it has where the idle fluctuates up and down. The smoke from the exhaust also subsides. I recently bought this car, so I don't really know much about them or their tendencies. Anyone got any ideas? I'd like to figure this out myself, I'm quite the poor college kid, and my car knowledge is pretty limited. Thanks for the help everyone.