I have a 99 GTP and when at highway speeds when I go to pass and pull out and give a decent amount of gas the boost gauge does to full but it just slowly accelerates and doesn't feel right. Does start to accelerate quicker. Previously it would actually shake, but I replaced the plugs and that went away. Since then I've replaced the wires as well and the fuel filter and cleaned the MAF sensor. No codes are being set. What's the next thing to try replacing - the coil packs? Don't really seem to notice it when say stepping on it from a stop light.
