2000 1.6 . Just bought. Engine loses power when throttling. Graph shows (+) 7-9 degrees advance timing at idle. When throttling 500rpm upwards to 1500 rpm graph shows (-)15-18 degrees. No MIL light. All management controls are in parameter. Exhaust Mani. gets cherry red after a five minute drive! NO exhaust obstruction. I found the Cat. to be gutted. Also ECU has been replaced w/used. When O2/#2 sensor is disconnected, MIL light is not triggered, however MIL light triggers when all other management components are disconnected. Can anyone point me to suspect?