Hello to everyone here at GPforums, this is my 1st post. I have a 99 GTP with 152,000 miles, its had a recent tune up, plugs, wires, fuel filter ect....My wife normaly drives this car and i am just finding out after a 600 mile round trip that the supercharger isnt working. the boost guage only goes up a 1\4 of the way at full throttle, no whine and the motor feels dead. Just had the converter and resinator replaced before our trip and got an average of 27 to 28 mpg. I need help diagnosing this problem? Please help!!