I have a 2003 trailblazer and have been battling for months with a “reduced engine power” light. I have no throttle. I replaced the gas pedal, the ecm, and the throttle body. I spoke to a mechanic yesterday and he said that I need to erase all the codes to get the proper relearn. How can I erase the codes, I have a cheap code reader, but it doesn’t erase.