Skip the auto shop - Our mechanics make house calls

Q: Code P0171. Do I need to take car to dealership to address this problem.

asked by on

I have replaced spark plug wires, fuel filter, mass air flow sensor and it still runs rough.

My car has 165000 miles.
My car has an automatic transmission.

Hey there. It sounds like your throttle body is bad. Check to make sure it’s clean and not sticking. Clean the throttle body if necessary and check for loose connections with the throttle body connectors, too. Since you said that you replaced the wires, make sure you have all of the connections properly seated and in the right place. If you need to have this checked, a qualified professional from YourMechanic inspect the rough running in order to have this properly taken care of.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  • Home
  • Questions
  • Code P0171. Do I need to take car to dealership to address this problem.

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Air conditioner works but not fan

Hello. If the air conditioning system is working, but not blowing air, then there may be a problem with the blower motor, or perhaps one of it's associated components. The blower motor is often located inside the dashboard, and sometimes...

Q: Loss of power, takes longer to start.

Hi there: Anytime coolant freezes inside an engine, it's typically due to the fact that it's percentage of water was too high. When this occurs, it can cause seals, gaskets and even metallic components to crack or break inside the...

Q: My car wont stay running

Anytime a car has been modified, it is tough to give valid advice from a keyboard. There is just no way to know what has been done. I can give you some general advice however. I would first suspect...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...