Check Engine light is on. on 2004 Chevrolet Malibu

I replaced the entire exhaust system from the cat back this spring and replaced both o2 sernsors. Check engine light is still on???

Asked by for the 2004 Chevrolet Malibu
what code??

p0133 and p0135
the heaters for the sensors are controlled by a fuse. you need to check it. it may have been one of the sensors that had a bad heater and you fixed it with replacing the bad one. look for the fuse first. if it is ok, then there is another issue. stop replacing parts till you have someone tell you the problem. it gets expensive replacing parts that are not bad.