Alright i recently changed my spark plugs and wires. As soon as i did, my 95 thunderbird lx v8 4.8l started idling really hard, it sounds like its backfiring, andit definetly doesnt have the power that it did. ithas trouble getting speed.Coming from a complete stop it takes almost 30 seconds to hit 40mph. In order for me to drive on the freeway i have to put the pedal to the metal. I made sure that I didnt mess up the timing... I dont know whats going on, can somebody help me!!!


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First thing I'd do is make sure I put the wires back on the same way they came off. Swapping 2 wires can cause this by having the spark arrive at the wrong time. Another is a broken plug, being careful not to crack the insulator during install.