My 7's ideal was bounceing...a lot. Brought it in for it's E-test and founf out I needed to replace the mufflers, and there was a bad gasket at the cat. Now that, that's all fixed it ideals properly. Why is this? Is it proper back presure, or???

 

First off, LOVE the color dude... I'm a sucker for blue cars.

Second, I don't think I've ever heard than an exhaust leak actually caused a bouncing idle. Usually the pulsating/surging/rough/bouncy idle is the result of the Throttle Position Sensor going bad or out of adjustment, a vac leak or Mass Air Sensor failure.