Toyota Repair: surges, mass air flow sensor, mass air flow

Question
Hi, i have a 2005 collolla S. Brought it to two dealer ship because it surges when it is cold and the car lacks power, at time works great. Changed the coolant temp sensor, cleaned the mass air flow sensor, unpluged battery to reset comp and nothing, next i was going to put a new o2 sensor, was talking to a guy at toyota dealer and he said they will flat line and give no check engine light, any suggestions??? thanks.

Answer
If the









If the O2 sensors fail it will trigger a check engine light, the sensors can be tested using the diagnostic scantool, can you tell me what the trouble codes were when the check engine light came on or is it on now?