How about a simple first aid by removing positive battery cable for about a minute, while engine is shut off, It might just reset ecm and goes back to original value. It doesnt cost a penny and you will know immediately, if there is definitely something wrong with the electrical system, sometimes simple solutions are being overlook. I can almost bet it will fix the problem. Dont forget that most of the sensors are tucked in. I still have to see 1 that fails unless it already failed before install.
RIDING RELIEVES MY STRESS FROM WORK