P1133 Chevrolet - 03 Trailblazer

Question

engine idiling at 900 rpm and loosing power. i already replace both 02 sensors

Answer 1

The 02 sensor is just reporting the condition of the vehicle. if the engine is loosing power you have a lean condition and this would result with P1133 , Lean conditon can be from a MAF (mass air flow) not reporting correctly, to a low fuel pressure condition. Do a throttle body and a MAF cleaning , it may help to resolve the issue .