Q: Rough idle, possible misfire, bad oxygen sensor a possible cause

asked by on December 22, 2016

For a while my truck has idled and drove roughly and then died, replaced the fuel pump and that solved the starting issue, but my truck still idles roughly, not nearly as bad as a bad fuel pump, but still rough; yes the check engine light is on, says both cylinder banks lean and a possible misfire code in cylinder 1. I was wondering if a bad oxygen sensor could cause a misfire and of course a rough idle and the lean codes. Any help is much appreciated.

My car has 147177 miles.
My car has a manual transmission.

Oxygen Sensor Replacement $108.80 - $869.59 Get a Quote

There are a number of things that can cause a misfire to be present, but a failing oxygen sensor is certainly one of them. As you know the oxygen sensor reads the exhaust gases and relays this information to the computer which then makes adjustments to the fueling of the motor. When this is not working properly, this may cause inaccurate readings to be sent to the computer resulting in improper fueling adjustments to be made. This will no doubt cause an erratic idle and in some cases cause a misfire depending on the adjustment made. I would recommend having a professional from YourMechanic come to your location to diagnose and inspect your truck.

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