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p040b

  1. Check Engine Light, Error code P040B?

    Generation 2 Volt (2016-2020)
    Advice? Steady Check Engine Light came on yesterday at 1035 miles. Error code: P040B problem with emission system, engine exhaust. The car seems to drive fine, no problems I can observe. I put my first gas in Saturday at 998 miles, so is it possible that it is due to a loose gas cap (now...
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