What other possible fixes for P0155 after replacing the O2 sensors?

Question

I get a service engine soon light on my vehicle. The code shows P0155. I have replaced all O2 sensors. It still comes on with P0155 code. What other possible solutions to fixing this problem? I have replaced the idle air control valve, throttle position sensor, MAP sensor, MAF sensor, all fuel injectors, vacuum check is good, PVC valve replaced, fuel filter replaced, fuel lines cleaned. ECM was re-flashed.

Vehicle idles low, and inconsistent. Occasional misfire. I need ideas, spent a lot of money and the problem is not fixed yet, even though it appear to run pretty well most of the time.

Answer 1

There is either a poor ground condition or there is a short in the harness. The wiring harness will have to be checked.