po300 issue
 

Im having a po300 code and cel on. 2011 370z Nismo. 32000 miles. Car sits alot. cel comes on. ,Increased idle 1000-1100 rpms. Outside of the high idle car runs fine. Its in the shop now. but owner isn't to sure what direction to go forward. im going to have them check for vacuum and air intake leaks. also exhaust leaks. Only mod is fast intensions exhaust. factory cold air intakes, No cats on car. Theres all kinds of reports on here so its frustrating at best, all original plugs and coil packs . THX D

car displayed two codes. po300. and po171

What kinda shop did you take it to, a simple internet search comes up with.

Common Problems That Trigger the P0171 Code
Control module software needs to be updated
Vacuum leaks (intake manifold gaskets, vacuum hoses, PCV hoses, etc.)
Mass air flow sensor
Plugged fuel filter or weak fuel pump
Plugged or dirty fuel injectors

Common Misdiagnosis for the P0171 code
Oxygen sensors

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