Q: P0171

asked by on October 06, 2016

code P0717 keeps coming up sporadically. When the "check engine" light comes on the car shifts rough but when it goes away it runs fine. I checked the resistance of both input and output sensors and they both register the same 623 omhs. I don't mind replacing the sensor or both sensors but I'm not sure if that is cause of the problem. Do these sensors go out gradually or suddenly? Any suggestions?

My car has 86000 miles.
My car has an automatic transmission.

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Oxygen Sensor Replacement $123.80 - $932.74 Get a Quote

Hi there. This code you are getting is due to your system running lean. Most of the time, it is caused by low fuel pressure from a weak fuel pump or a clogged fuel filter. Another possible cause can be due to dirty injectors. I usually check these potential issues first to see if they are fine before checking the oxygen sensors. If the components turn out to be defective, they will need to be replaced. If you need this P0171 code checked, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair anything that is needed.

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