Ford Fiesta owners have reported 2 problems related to o2 sensor (under the electrical system category). The most recently reported issues are listed below. Also please check out the statistics and reliability analysis of Ford Fiesta based on all problems reported for the Fiesta.
Took car to mechanic to have O2 sensors replaced at time of oil change. Auto shop completed oil change and changed O2 sensors, reset check engine light, but then car wouldn't start. Mechanic reassessed, found blown fuses in fuse box, noting dirt in fuse box and corrosion. Car was towed to Ford dealership for further diagnostics as auto shop stated they couldn't do anything for Ford ecu. Ford ran detailed diagnostics to again find that dirt and corrosion in fuse box led to malfunctioning and car not starting.
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all problems of the 2011 Ford Fiesta
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The car evap purge valve stays open. The car idles and dies everytime I put gas in. The purge valve was replaced less than a year of purchasing the car and it's gone bad again. The check engine light and engine malfunction warning came on then two days later the car died after I added gas and took 2 hours to start. I bought a new battery and drove it another week. It still idles after adding fuel even with the new battery. It finally died and I had it towed to the Ford dealer and they did a diagnostic and said the catalytic converter, throttle body and evao purge valve, O2 sensor is bad and all 3 needs replacing.
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all problems of the 2017 Ford Fiesta
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