i have an 02 gtp and it feel like it has lack of power. it used to be alot more powerful but not any more. i have changed the cat a while back when the problem first started and it improved. but it sill guttless. it also seems to burn alout of fuel too. what could the problem be. the car has 217000kms on it. i was thinking the downpipe may be colaped inside. bad o2s. i also noticed 2 that wen you dive the car hard the rear maniflod neer the frt of the motor turns red like heating it with a torch. are downpipes common to collapse. and should it be burning so much fuel. it tells me its doing 15 to 16 l per 100 kms. i scanned it it has no codes and the engine light has never come on since i have owned it. when i replaced the cat i cut and welded an aft one in it still has the fact down pipe. what could this be? has anyone had this problem or a simlair one to it thanks.
