Look for a vacuum leak.
If the car is have issues accelerating it may be running to lean. Ensure the engine is using the proper air to fuel mixture so the car will not run lean.
Your car may stall or stop running after idle because of a problem with its fuel or electrical system.
p0171 andpo174 mean that you're car is running lean
Yes.
when i get out of car the aircon stays on how can i stop it
14.7:1 --- Air : Fuel Ratio. perfect. not lean, not rich.
Look for a vacuum leak.
Bad ecm
it sense oxygen come out from your engine to tell the PCM your car is running rich or Lean
If any car backfires it is usually due to retarded timing, running lean or a problem in the valve train.
can a bad altenator make my computer in my car to stop running