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Honda accord 91 EX?i recently had another engine out it. but the engine runs good. my car is an stick and the enging was an auntomatic but everyone has told me that it doesnt matter. okay have two questions. first my idle on my car is going up and down when the car is stopped. it doesnt go pass 2 or anything though. a local mechanic switched out the computer but it is still doing it. what could it be?Also my car will be driving down the road and start to slow down even when i my foot is still on the gas. then i will move my foot off and tap it a couple of times or hold it all the way down, and then it will jump in and take off. everyone has thought okay fuel pump or filter. but i have had all of that changed. also there is no water in the tank. please help me!??