ok I have a 2000 GTP GP and I am getting really bad gas mileage averaging 15-16mpg I know driving style greatly effects gas milage but I get better gas mileage in my GTO so what I need to know if what mechanically will effect gas mileage I have auto lite 104s in it which is 1 heat range cooler I have a custom build 3in fender well intake and thats it please help me solve my puzzle?????

are you sure it'* a GXP? those didn't appear til 05 in the GP i believe

lol sorry about that had GXP on the mind meant GTP

I would check the O2 voltage and if it'* not toggling quickly, replace the O2. That'* the most common contributor to bad mileage. There are a few other things like vacuum leaks and plugged catalytic that can also cause it.

GTP Steve.

Remember winter blend is going to drop mileage a bit. 18 to 20 is about what you can expect. So your really not that far off. But you can check your coils, check for vacuum leaks, check your fuel filter, add some injector cleaner, and check to make sure your TCC is locking at highway speeds (over 47mph). You can also replace your O2 sensor if it'* old.

i know he edited it hehehehe

how does one check to make sure the TCC is locking

Get up to highway speeds, and cruise, then hold your foot on the gas to hold the speed, and then press the brake peddle a bit, if the RPM jumps a bit, the TCC just unlocked.

ok i will check that tonight and as far as the cat goes can i just remove it also is there any reason to have a wide band O2

If you have emission testing, the cat will need to be there. A wide band O2 is for tuning, other then that it will only tell you your AFR, which does you no good unless you can do something about it threw tuning.