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Q: Had new Mass airflow sensor put on an now I'm getting a code p0171 what could it be

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in the morning I start it up an it start putting an shut off but starts back up gotta put it in drive when warming up

My car has 158000 miles.
My car has an automatic transmission.

A: This relates to a lean fuel condition which...

This relates to a lean fuel condition which can be caused by many different things such as:

  • Intake air leaks
  • Faulty front heated oxygen sensor
  • Ignition misfiring
  • Faulty fuel injectors
  • Exhaust gas leaks
  • Incorrect fuel pressure
  • Lack of fuel
  • Faulty Mass Airflow (MAF) sensor (You already replaced, so it should not be this)
  • Incorrect Positive Crankcase Ventilation (PCV) hose connection

I would recommend having an expert from YourMechanic come to your home to diagnose your trouble code firsthand and help you repair it as necessary.

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