Chevy Cruze P0171 Code: What It Is And How To Fix It (2024)

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Ursachen, Anzeichen und wie man ihn behebtChevy Cruze P0171: Causes, Diagnosis, + How to Fix | Drivetrain ResourceCode P0171 - System Too Lean: Symptoms, causes, common problems, diagnosticChevy Cruze: What is the P0171 Code? - VehicleHistory

Cruze Sedan

Make

Chevrolet

Segment

Sedan

Last on sale for the 2019 model year, the Chevrolet Cruze scored over 1.8 million sales in the USA before the popularity of SUVs guaranteed its demise. These sedans were equipped with a variety of powertrains, including a 1.4-liter four-cylinder turbocharged mill and a 1.8-liter four-cylinder naturally aspirated engine. It's these two engines that were prone to triggering the P0171 error code, which indicates a lean condition on bank 1, whereby the air-to-fuel ratio contains either too little fuel or too much oxygen. We've covered the P0171 error code before, as it applies to all vehicles, but this time, we'll take a deeper dive into the specifics of this common fault code that plagues the Chevy sedan.

What Does The P0171 Error Code Mean?

The P0171 error code indicates the engine is running lean. The powertrain control module (PCM) monitors the oxygen content of the exhaust post-combustion. If the Heated Oxygen Sensor (HO2S) indicates higher levels of oxygen content, the PCM makes adjustments to the injector pulse to balance their-fuel ratio. This adjustment occurs constantly while the vehicle is operating. The P0171 error code is set when the weighted average of the adjustment differs from the calibrated value. In simple terms: the PCM sets the P0171 error code when there's too much oxygen content or too little fuel in the air-fuel ratio.

What Causes The P0171 Error Code?

The PCM can set a P0171 error code for several faults. The most common faults for the P0171 error code are:

• Worn spark plugs
• Defective engine valve cover
• Faulty oxygen sensor
• Faulty manifold absolute pressure sensor
• Faulty fuel injectors
• Defective mass air flow sensor

The following are all potential faults that can cause the Chevy Cruze to set the P0171 error code:

• Vacuum hoses with splits, kinks, and improper connections
• Insufficient amount of fuel in the tank
• Low fuel pressure
• Fuel contamination
• Malfunctioning fuel injectors
• Missing, loose, or leaking exhaust components from the HO2S forward
• Vacuum leaks at the intake manifold, the throttle body, the brake booster hose, and the injector O-rings
• Leaking air induction system or air intake ducts
• Missing air filter element
• Cracked Evaporative Emission Control (EVAP) system canister
• Evaporative pipes obstructed or leaking
• Leaking crankcase ventilation system
• Improperly installed HO2S
• HO2S electrical wires or connectors that may have contacted the exhaust system
• The B52A Heated Oxygen Sensor 1 sensor 1 signal circuit open, shorted to ground or shorted to the low reference circuit
• The B52A Heated Oxygen Sensor 1 sensor 1 low signal circuit for an open circuit or high resistance
• Malfunctioning engine components

Symptoms Of The P0171 Error Code

The most common symptom reported by Chevy Cruze owners is the Service Engine Soon (SES) light, which will be illuminated. Other possible symptoms Cruze drivers may experience are:

• Poor engine idle
• Engine stalling
• Loss of engine power
• Delayed throttle response
• Reduced fuel economy

Can I Drive My Chevy Cruze With This Issue?

The P0171 error code won't stop your Cruze from going down the road. However, there are a few concerns to note. If your Cruze is setting the P0171 error code, it will not pass emissions inspections, you'll experience reduced fuel economy, and your engine can suffer a lack of performance, a potentially dangerous symptom. We recommend you fix the P0171 error code as soon as you can and prevent long-term continued operation.

How To Fix A P0171 Error Code On Your Chevy Cruze

According to GM's Technical Service Bulletin (TSB), an improperly seated oil fill cap or dipstick tube can be the cause. We recommend checking this first, especially if your Cruze had recent maintenance performed. If your engine oil cap and dipstick tube are properly seated, we recommend you focus on the Positive Crankcase Ventilation (PCV) system first.

The PCV valve hoses can break and crack, causing unmetered air to be drawn into them. You should carefully inspect the PCV hoses connecting the engine valve cover to the intake.

AllData's Find-A-Fix reports one of the most common repairs as an engine valve cover. Because the Cruze integrates the PCV valve into the valve cover, it does not offer a replaceable PCV valve requiring valve cover replacement.

In our general piece on the P0171 error code, we also covered how you can identify a lean engine in more detail.

How Much Does It Cost To Fix?

Due to the frequency of the P0171 error code for Cruze owners, repairing the fault should not take too much diagnostic time or labor.

There's always the possibility that your vehicle doesn't suffer from the typical faults. Repairs such as intake gaskets and worn fuel pumps can add up to a costly repair bill. A fuel pump replacement on your Cruze can run up to $750. Intake gaskets are not as expensive with replacement coming in between $200 and $400.

With the majority of repairs being spark plugs or valve cover replacements, fixing the P0171 error code on your Chevy Cruze shouldn't hurt too badly. Using the most common repairs, you can expect the cost to be anywhere from $25 to $200, according to RepairPal.

*Note: GM has updated the part number for the valve cover three times. Make sure you order the latest version.

Component Cost Estimates