P0135 Nightmare

[NOTNEKASURVAV]

2000 z28, auto, headers,no cats, slp intake Car Runs like crap, can someone take a look. and hopefully point me in right direction
first tune is what ive been running for about a year. the other is tune being used when i bought the car.
just wondering if there might be a different issue.

tunez.hpl stockz.hpl

[DougO]

Have you checked the wiring from the sensor to the ecm? I'm assuming your exhaust doesn't have any leaks. I'll assume you've swapped the sensors from side to side. Need more info on what you've done to eliminate the issue. Post your tune as well.