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P0171 is a diagnostic trouble code (DTC) for "Trouble Code Help Schedule Inspection & Repair". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic for $169.99 . Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $50.0 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.
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The P0171 is a diagnostic trouble code (DTC) that means, 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.
The P0171 code is a serious issue and continuing to operate the vehicle while this code is set is unsafe. If a vehicle has this code stored in its powertrain control module (PCM), the engine of that vehicle simply will not run well.
If the engine does not maintain proper air/fuel ratio, there will be a major waste of fuel and a lack of power while driving. It is a good idea to have this code diagnosed and repaired as soon as possible to have your vehicle running smoothly.
Some common symptoms you may notice in your vehicle when the P0171 code is set include:
Some common causes of the P0171 code may include:
The most common repairs needed to fix the P0171 engine code are as follows:
Here are the general steps a mechanic from YourMechanic will take when diagnosing the P0171 code:
Assuming that no other trouble codes exist, the mechanic may diagnose the P0171 code by checking the engine for vacuum leaks with a vacuum gauge. A vacuum leak will create a hissing sound usually only audible when the engine is turned off.
The fuel pressure sensor and MAF sensor (mass air flow) will also be checked with a fuel pressure gauge.
In order to maintain a proper air/fuel ratio, the vacuum and fuel pressure of the engine must be within the manufacturer’s specifications. The cause of the P0171 trouble code will likely be discovered during one of these two tests.
If the cause of this issue is still not found after the mechanic has performed these two tests, the problem likely lies with a sensor.
The mechanic would then run tests on the mass airflow sensor and the oxygen sensors using the manufacturer’s procedure.
If all of these tests have been performed and no issues are found, the problem is likely the powertrain control module.
A mistake that often occurs is not looking for any technical service bulletins for your specific car model that may be related to this issue. Although not every trouble code will have a technical service bulletin associated with it, it is always wise to check. They can save you a world of time and effort.
It is unwise to drive a vehicle with this trouble code stored for a long period of time. If an engine runs improperly for a long period of time, further damage may result that could end up being much more costly to the owner of the vehicle.
If your P0171 code is set, contact YourMechanic below to get a quote and an inspection from a mobile mechanic in your area immediately.
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