I was going to say it could be a fuel issue, which to me sounds like a logical explanation. Considering my POS na liberty suffers from quite audible detonation on a hot day, even using a tank of 95. Add a turbo to the mix and things aren't looking good in terms of making much power. Also how did you come onto power? Did you just stab the accelerator or ease it on? How does the car run on a day like today? (22' or so)

Kaya.