Hello guys!, I’ve got a 2002 Tahoe 5.3 flex fuel Z71. My problem is that about every 200 miles my service engine soon light comes on. When I check codes it’s PO157, o2 sensor circuit low voltage bank 2 sensor 2. I’ve tried to fix this by replacing the o2 sensor after the cats on the drivers side. Cleared the code and after another 200 miles it popped back on again. So I went chasing the exhaust system looking for leaks, and found 3 of my exhaust manifold bolts broken. Used some aftermarket exhaust manifold clamps to seal up the leak and again reset the code. Well today it popped back on again. Should I be worried about fixing this? Having a light on the dash drives me crazy. What would yall do from here?