1. It had no light before when It passed emissions Test PRIOR to have engine rebuilt (stuck valve stem; new pistons, timing chain, sparks, cables, wires, dist. cap, rotor, oil pan, gaskets, ETC).
2. Muffler has hole in it. Hole WAS ion there before the engine repair.
3. Gasoline consumption is greater now.
I took to “magicians” that repair engine and they told me “the scanner shows O2 sensor” but did not provide a code reference (I think they just made it up, because they do not know enough electronics for this).
Any ideas?
