Is your engine throwing a misfire code? The problem is generally a failing or dead coil pack. Coil packs are what give your vehicle the spark to make the power, and if the spark is weak or nonexistent, power will decrease as your engine misfires. Restore that lost power and eliminate the misfire and replace yours now, an easy fix that can give your vehicle a performance rejuvenation and better fuel efficiency.
If you are replacing any aspect of your ignition system, it's best to replace all serviceable components. By doing so, your ignition system will work in better harmony, freeing up hidden horsepower and raising fuel economy.