Q: Code P0171?

asked by on July 23, 2017

Just got my car out of the shop and they replaced the head gasket. Today my check engine light came on so I took it to auto zone and got the code read. It says "Code P0171 indicates that the Bank 1 System is too lean for a predetermined period of time." When I left autozone the check engine light turned off. The car is running normally. Does this have anything to do with the head gasket? I don't know anything about cars but I thought that maybe the code for the head gasket was still on there and reading it turned it off. What could this be?

My car has 168000 miles.
My car has an automatic transmission.

Hi there. The P0171 code means that, on the first bank of the engine, the fuel system is running weak or a vacuum leak exists near this side of the engine. A lean condition occurs when the engine either receives too little fuel or too much air. You might want to read this article about this error code to review the possible sources and causes of this problem. Generally speaking it would not be related to the actual head gasket replacement. However, it is possible that they forgot to attach a sensor connection or other component during the service, so I would contact them about this error code to see if they’ll resolve the issue.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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


Experienced Mechanic?

Earn up to $70/hr

What others are asking

What does the AdvanceTrac off Warning Light mean?
The AdvanceTrac off Warning Light is located on the instrument panel. This light illuminates when you have manually turned off the AdvanceTrac traction control system. When you turn the system back on, the light will disappear. Tip The AdvanceTrac off...
I was driving and when I tried to make a turn my steering wheel was hard to turn. Soon after my car cut off.
Hello. It is very possible that the timing belt broke or the engine seized. I would usually check the oil level (https://www.yourmechanic.com/services/oil-level-is-low-inspection) first. If it is empty then there is a serious issue. If there is oil then I would...
Changed the power steering pump and tensioner but I still have a clicking noise when the car is running.
Hi there. Before changing anything else, remove the serpentine belt and start the engine to see if the noise goes away. If it does, then it definitely is coming from somewhere on the drive belt path. Investigate the pulleys and...
Car just won't move forward or reverse.
Hi there. When your vehicle cannot move, put the transmission in park and then in drive. See if the engine is loading up and the rpm's are dropping. If they are then check the brakes and see what is causing...
Water leaking from above thermostat i believe help. 1995 Toyota 4Runner V6
Hi - finding coolant leaks (https://www.yourmechanic.com/question/leak-in-my-cooling-system-by-kalah-w) like this requires a careful eye. Tight engine packaging, and the fact that slow leaks can evaporate quickly, make it more difficult to determine the source of the leak. A leaking hose connection at...
I have gray smoke coming out of my tailpipe but it's not heavy smoke and my car check engine light is orange​ my car shut off
You did not mention why the radiator was replaced but I think your engine was overheated causing the head gasket to go bad. This would cause the white smoke out of the tail pipe and an engine misfire and overheating...
Where is the crankshaft sensor on a 2011 vw cc sport 2.0
The crankshaft sensor is in center of motor near flywheel even with starter on engine block.
Ford Expedition no Crank no Start
With the key in the start position, if the relay in the solenoid circuit works, the thing to do is measure the voltage drop across the relay and also the voltage drop in the circuit to the starter motor. If...
Grinding noise while driving 2013 Ford F150
Here is a tech bulletin for the noise and a fix. click here (https://www.dropbox.com/s/itfnfbvxsmie2ap/2013%20f150%204x4%20noise.pdf?dl=0)

Related articles

The Best Used Cars to Buy for Occasional Drivers
Not Not everyone relies on their car on a daily basis. Maybe you aren’t the type that deals with a daily commute, and running from here to there constantly. If that’s the case, you may be looking for a car...
Pontiac Certified Pre-Owned (CPO) Car Program
If If you’re in the market for a used Pontiac vehicle, you may want to check out cars under their certified pre-owned program. Many manufacturers have a certified pre-owned (CPO) program, and each one is set up differently. Read on...
How to Buy a Classic Pontiac
Whether you want to buy a classic Pontiac for yourself or as a gift, here are some tips on buying one for a great value.