Q: The p0420 code came up, and my car was jerking on my way home, at around 50mph. Is this a clue to my p0420, or a new issue

asked by on February 04, 2018

Essentially i had my engine light come up on my 2006 chevy cobalt 2.2. I got it erased and it came back a week later. (Its still only been a week since it initially came on) and i was just driving home and my car was jerking really oddly. Jerking as in i'd keep a steady speed then it would momentarily lag like a bad connection. My fuel econ reader says im getting 8.8 so atleast my fuel consumption is still good. So I wonder if this is apart of my p0420 code, or if it's the symptoms to something else wrong with my car. Would this jerking and my fuel economy say that the o2 sensor is the likely culprit? And i am not asking for definitive answer, i know you guys can't say things without knowing for sure because someone can say "your mechanic told me it was this, its all your mechanic's fault." So I understand the answer you give me is not 100% fact and nor do I need it to be. Just want to know if maybe my p0420 and jerking might be connected possibly.

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The code you are writing in about might be related to the engine misoperation and low fuel economy. Diagnostic Trouble Code P0420 has many, many potential causes including a damaged muffler or leaks in the muffler, damaged exhaust manifold or leaks in the exhaust manifold, damaged exhaust pipe or exhaust pipe leaks, misfiring in the engine, oil contamination in catalytic converter, a faulty catalytic converter, a faulty engine coolant temperature sensor, faulty front oxygen sensor, faulty rear oxygen sensor, damaged oxygen sensor wiring, oxygen sensor wiring that is not properly connected, damaged oxygen sensor connectors, a fuel injector that is leaking, fuel pressure that is high, and other causes. The only way to determine which of these faults is the cause is through a diagnostic. If you desire that this problem be diagnosed by a certified Mechanic, dispatched by YourMechanic right to your location, please request a check engine light diagnostic - code P0420 and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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