1997 civic ex d16y8 and a 5 speed. mods, CAI and exhaust of some sort, PO did it.

so i was driving to work on the freeway and all of the sudden my car just starts to bog out. i was losing speed and couldnt gain it back. anytime i pressed more than just barely on the gas peddle it would bog again. only way i can describe the sound is it sounds like an STi. that rumble of a boxer motor. it will only act this way once the car has been running for a while and its fully warmed up. but not right when it warms up. its got brand new plugs and wires so that issue can be ruled out. also when idling it sounds as if the TPS is outta wack, the random dip and rise of the idle. but its not tps. also i can get the car to accelerate faster if i roll into the throttle. but i have to do it really slowly

also the colder the motor is the better it runs.

am i just over looking something stupid here?

knowing my luck its something real bad, the cel light never comes on, even if you unplug stuff. the OBD port doesnt work either for some reason. so i had to use the plug under the kick panel to see what code it was throwing.

the code will come back no matter what even if i clear the codes. car has new plugs wires coil and fuel filter since these were the first suspects. now im outta ideas. hopefully someone can help!!!