QuestionI have a 2004 Nissna Sentra. For the last several years, it has been harder to start in the summer. In the winter, it would turn over in 1 or 2 cranks. However, in the summer, it would take 4-5 some days. I just figured it was cold natured. Anyway, a week ago, my wife got frustrated and pressed on the gas when it didn't start up right away. The check engine light came on. I put a diagnostic meter on it and it read error code P1148. The error code read maufacturer control fuel air metering. Looking on-line, they were talking about front heated bank-1 O2 sensor. A" closed loop control fault". What does that mean? There are 2 different O2 sensors in the car and I don't know which one needs to be replaced. Help.
AnswerHi David -
Closed loop means when the engine is warmed up. While the engine warmns up before the thermostat opens it is in "open loop" mode.
Bank 1 means the passenger side of the vehicle.
During the closed loop mode the ecu uses information primarily from the Oxygen Sensor and adjusts fuel delivery and timing to achieve minimum emmisions, better gas mileage and power.
So it appears that the O2 sensor may not be conveying correct info to the ECU. I would check again if there are multiple codes, as if it is the O2, it also had a separate code.
Autozone does this, and I think is is a free service.
Hope this helps
aloha
calvin
