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Q: I have a 2005 chevy malibu automatic transmission, 4cylinder,

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my engine light came on ... code P0171, I also had the engine power reduced reading, I was driving the freeway went to pass and started loosing power engine light come on flashing then reduced engine power reading come on then car begain to run rough wanting to die as if out of gas. I pulled off road shut car off and restarted it ran fine. I do have loss of gas mileage from what I had before any suggestions of what this would be. code reading P0171 shows oxygen sensor, ignition misfire, fuel injectors, I am pulling more of the misfire due to car wanting to die, and due to loss of gas mileage, but I'm at a loss, could this be due to maybe a bad ignition coil ? Is there any true way to find out exactly what this would be caused from without repairing multiple things to get it fixed.

My car has 130000 miles.
My car has an automatic transmission.

Hi There, Code P0171 relates to the oxygen sensor reading an incorrect amount of oxygen in the exhaust gases. This combined with the poor fuel mileage and loss of power or wanting to die suggests that this may be caused by a faulty mass air flow sensor. The mass air flow sensor monitors air intake as it is mixed with fuel prior to being injected into the motor. This sensor relays vital information to the ECM which uses this to make adjustments to fuel supply to the motor. A dirty or faulty sensor can cause an imbalanced air/fuel load to be supplied to the motor which results in an over fueling or under fueling situation depending on the conditions. This type of inconsistent fuel supply to the motor may cause a hesitation, loss of power, a jerking reaction, potentially a bit of black exhaust smoke and typically a strong smell of fuel when this sensor is malfunctioning. I would suggest having a professional from Your Mechanic come to your home to diagnose and inspect your vehicle.

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