Code 7 (pm6), Backfiring

[RFHOMI2U]

PLEASE HELP!!!! My motor is breaking up/cutting out/backfiring when in high rpm's (about past 5,000) and my ECU is throwing a code 7. I hollowed out my Cat, and it didn't help. What does the code 7 mean, and what else could my problem be???

 

[monzee]

Defective TP sensor (throttle position). Info from my ecu trouble code list.