I have a 1992, Ford, Tempo, 2.3L, Automatic, 83,000 original miles. When it is idling at a stop sign or even when it is just idling in park, it idles rough and the car shakes. I hooked up a computer reader from Wal-mart and it said that number 1 cylinder is not contributing equally. I put 4 new spark plugs in, put 5 new plug wires on, new air filter and it still hasn't fixed the problem. Any help would be appreciated.