P0171 ford

The most common cause of the P0171 DTC is having an aftermarket intake that is not tuned for. Other common causes include vacuum leaks, exhaust leaks, a clogged fuel system (injector, pump, regulator), or faulty MAF, O2, or fuel pressure sensors. Most often it is an intake or vacuum leak causing the code.This article will help you to diagnose diagnostic trouble code P0171 (System Too Lean Bank 1) and/or P0174 (System Too Lean Bank 2) on your Ford, Mercury or Lincoln 4.6L or 5.4L equipped car, pick up, van or SUV. Although you can apply this info to any Ford vehicle with a V6 or V8, this info concentrates on the Ford 4.6L and 5.4L V8 … The P0171 code on your Ford vehicle indicates a system too lean condition in bank 1. This means that the engine is receiving too much air and not enough fuel. To diagnose and fix this issue, you should start by inspecting the intake system for any leaks or vacuum hose problems. Additionally, you may need to check the Mass Air Flow (MAF) sensor ... Ford tractors can be identified by the serial number that has either been stamped behind the oil filter on the engine block’s left side, on the left side of the transmission case, ...My problem is the Check Engine Light in on, and I am getting the P0171 code. I have read everything on this forum about eliminating the code, and have performed the following steps: - new fuel filter - no change observed. - new spark plugs - no change. - cleaned MAF sensor - no change.Ford explorer 4.0l v6 sohc p0171 p0174 lean codes- common cause P0134: o2 sensor circuit no activity detected (bank 1, sensor 1) What would cause obd-ii error codes ...There may be other very specific (or common) issues that other motorists have experienced with your car. Just Google the codes followed by your car's make and model, for example: "P0171 and P0174 Ford Expedition." As one example, many report that a common cause of the P0171 and P0174 lean mixture fault in the BMW X3 is a faulty …Whether you already own a Ford vehicle or you want to be a Ford owner, you can find a Ford dealer near you to purchase a car or get service for the one you own. Use these tips to f...Fuel Injectors. P0171 indicates that your Ford Escape is either getting too much air or not enough fuel. A clogged or damaged fuel injector will cause the air-fuel mixture to lean out in one specific cylinder. You may see a cylinder misfire code or fuel injector-specific code with P0171.The most common causes of P0171 are a bad Oxygen sensor, a vacuum leak, or a dirty MAF sensor. Definition. P0171: Fuel Trim System Lean (Bank 1). Symptoms. Check engine light, decreased fuel economy, misfire, hard to find idle. Common Causes. Dirty MAF sensor, vacuum leak, O2 sensor.P0171 and P0174 are diagnostic trouble codes for lean condition in bank 1 and bank 2, respectively. These codes indicate that the engine is receiving too much air or not enough fuel, resulting in a lean air/fuel mixture. The potential causes include a vacuum leak, faulty oxygen sensor, clogged fuel injectors, or a malfunctioning mass airflow ...Jul 7, 2020 · P0171 and P0174 occur when the air/fuel mixture on the vehicle gets too lean. They are both thrown when the oxygen sensors detect that there is not enough oxygen in the exhaust. The engine then makes adjustments to compensate and throws these codes, which trigger the service engine soon light. When these codes both appear at the same time, it ... The most common cause of the P0171 DTC is having an aftermarket intake that is not tuned for. Other common causes include vacuum leaks, exhaust leaks, a clogged fuel system (injector, pump, regulator), or faulty MAF, O2, or fuel pressure sensors. Most often it is an intake or vacuum leak causing the code.Symptoms: P0171 + P0174 Ford Freestyle. There aren’t always drivability issues associated with these codes. For most people the first sign that anything is wrong at all is the service engine soon light coming on. Here are the typical symptoms that something is wrong when your Freestyle has codes P0174 and P0171.May 3, 2010 ... P0171 - System to Lean (Bank 1) The Adaptive Fuel Strategy continuously monitors fuel delivery hardware. The test fails when the adaptive fuel ...Feb 12, 2017 ... It is unusual to have both a lean and rich trouble code at the same time. In this video, I will show you the steps involved to identify this ...Jul 9, 2018 · Note that while “Bank 1” in this definition refers to the bank of cylinders that contains cylinder #1, code P0171 also applies to in-line 4 & 6 cylinder engines. NOTE: On V-type engines, code P0171 is often accompanied by code P0174, which refers to the same problem, but on Bank 2. If both these codes are present, the PCM has detected a ... Causes Of P0171 Code In Ford Vehicles. 1. Faulty Mass Airflow Sensor (MAF) The Mass Airflow Sensor measures the amount of air entering the engine to calculate the proper air-to-fuel mixture. If it’s giving incorrect readings, it can cause the engine to run lean. A code P0171 may mean that one or more of the following has happened: The MAF (Mass Air Flow) Sensor is dirty or faulty. Note: The use of "oiled" air filters may cause the MAF …Aug 31, 2023 · The Role of Oxygen Sensors in Identifying P0171 Code. The oxygen sensors are always monitoring how much fuel and air is in the mixture. If there is a vacuum leak, it can cause excess air supply to the engine bay. Then, the O2 sensors will detect a rise in air. Also, broken oxygen sensors can trigger the P0171 code. Descripción del código DTC P0171 FORD Ford. El código DTC P0171 en tu vehículo Ford indica que la proporción o mezcla aire/combustible no se está realizando de ...P0171 indicates that your Ford Flex is either getting too much air or not enough fuel. A clogged or damaged fuel injector will cause the air-fuel mixture to lean out in one specific cylinder. You may see a cylinder misfire code or fuel injector-specific code with P0171. If you have one or more fuel injectors that have gone bad, that can cause ...Popular Mechanics Magazine can recommend trying a few troubleshooting steps to resolve the P0171 code in a Ford F150. One technique is to check for vacuum leaks using a smoke machine or by spraying carburetor cleaner around the intake manifold and vacuum lines while the engine is running. Another suggestion is to clean or replace the Mass Air ...A P0171 code is set by your vehicle’s powertrain control module when the air-to-fuel ratio is too lean. This means that the engine is receiving too much air into the …Sep 13, 2010 ... I wouldnt be surprised if the EGR code(s) come back, as Ford EGR valves rarely go bad. Failed DPFE sensor is by far the most common cause of 401 ...Jan 15, 2018 ... Another case of P0171/P0174... · 1. Fuel system clogged/dirty. Check/replace Fuel Filter. · 2. Exhaust Leak. Check for leaks at the exhaust ...Fuel Injectors. P0171 indicates that your Ford Transit Connect is either getting too much air or not enough fuel. A clogged or damaged fuel injector will cause the air-fuel mixture to lean out in one specific cylinder. You may see a cylinder misfire code or fuel injector-specific code with P0171.P0171 code ford f150. P0174 p0171 diagnostic diagnosingP0174 lean failing pcm regulator injectors update P0171 p0174 diagnosing pointsFord trouble code p0611. P2197 code ford mustangFord p0171 and p0174 system lean P0174 code: system too lean (cylinder bank 2)Obd2 codes archives. Ford codes P0171 and P0174 indicate a lean fuel mixture problem, typically caused by vacuum leaks or a faulty mass airflow sensor. To diagnose and fix these codes, you can start by inspecting the intake system for any cracks, loose connections, or disconnected hoses. Also, check the air filter and clean or replace it if necessary. Your Ford's clutch switch, known as the neutral safety switch, prevents the vehicle from being started in gear. This safety feature is designed to avoid costly damage to your vehic...If the P0171 is combined with the P0174 code, the problem is likely caused by an intake leak or the Intake Plenum Gasket and seals. If there are no intake leaks ...One of the most common causes of the P0171 engine code is a fuel system leak. When your fuel system leaks, more air and less fuel will enter the engine's cylinders. This results in your engine running lean because it can't get the necessary amount of fuel. Another problem with the fuel system is clogged fuel injectors.P0171 - System to Lean (Bank 1) The Adaptive Fuel Strategy continuously monitors fuel delivery hardware. The test fails when the adaptive fuel tables reach a rich calibrated limit. For lean and rich DTCs: Fuel system. Excessive fuel pressure. Leaking/contaminated fuel injectors. Leaking fuel pressure regulator.The most common causes of P0171 are a bad Oxygen sensor, a vacuum leak, or a dirty MAF sensor. Definition. P0171: Fuel Trim System Lean (Bank 1). Symptoms. Check engine light, decreased fuel economy, misfire, hard to find idle. Common Causes. Dirty MAF sensor, vacuum leak, O2 sensor.Descripción del código DTC P0171 FORD Ford. El código DTC P0171 en tu vehículo Ford indica que la proporción o mezcla aire/combustible no se está realizando de ...P0171 code ford f150: meaning, symptoms, & fixesFord f series pickup p0171 p0174 lean condition codes Ford f150 pcv hose vacuum expedition 1998 valve 1999 elbow 4l heated 2001 v8 problem low exhaust 2000 p0174 assemblyTruck codes p0171 p0174 engine check light bought camper pull.P0171 indicates that your Ford Focus is either getting too much air or not enough fuel. A clogged or damaged fuel injector will cause the air-fuel mixture to lean out in one specific cylinder. You may see a cylinder misfire code or fuel injector-specific code with P0171. If you have one or more fuel injectors that have gone bad, that can cause ...Jan 29, 2022 ... I will show you some tips and tricks I learned while fixing the lean codes on my 2003 Ford F150 with the 4.2L V6. A perpetual P0171 code was ...Sep 10, 2018 ... Скорее всего это насос (может и фильтр-сетка на нем) или забитые форсунки (лучше чистить самому с заменой фильтров внутри форсунки). Можешь ...Trouble code P0171 & P0174 on a 2003 F-150 with 4.2L V6. I have cleaned the MAF, changed the fuel filter, looked for vacuum leaks, checked for vacuum leaks with the MAF cleaner (flammable), checked every thread on this forum, had the check engine light reset several times. The truck runs fine, just idles a little high when I first start it ...Modular V10 (6.8l) - P0171, System too lean, bank 2 - Hey folks, my truck is having a problem. I have the service engine light on and the code is: P0171, System too lean, bank 2. The guy at autozone cleared the light and said it probably just needed a good run down the interstate. I didn’t think I would be able to...The P0171 code is a generic powertrain code that indicates a lean condition in the engine’s air-fuel mixture. In the context of a Ford Ranger, it specifically points to Bank 1 being too lean. This means that there is either too much air or insufficient fuel getting into the engine on the first bank of cylinders.Hi Ed, P0171 and P174 are fault codes for being too lean (Bank 1 and Bank 2). Are you by chance running a MAFia and, if so, when you returned to ...This 2004 F-150 has leaned codes P0171 and P0174. Having both codes indicates that whatever is causing these lean codes is affecting both sides of the engine...I had a fuel smell and and engine miss. codes p1450,p0136,p0156,p1131. P0171 ford f150 code fix P0022 ford f150 5.4 code ford p0171 codes 1999 f150 sensors p0135 o2 How to replace maf sensor on ford f150 fix lean codes p0171 p0174Ford explorer 4.0l v6 sohc p0171 p0174 lean codes- common cause P0134: o2 sensor circuit no activity detected (bank 1, sensor 1) What would cause obd-ii error codes ...The "Check Engine" light was turned on yesterday on my '98 Expedition EB. I got two codes at the same time: 1. P0171- System Too Lean (Bank 1), and. 2. P0174- System Too Lean (Bank 2). I know either one of these codes can mean something is wrong with air intake, fuel system, or O2 sensor.Sep 10, 2018 ... Скорее всего это насос (может и фильтр-сетка на нем) или забитые форсунки (лучше чистить самому с заменой фильтров внутри форсунки). Можешь ...In a live interview on Twitter with Ford CEO Jim Farley, Elon Musk announced that Tesla will give Ford access to the network and adapters. Jump to Tesla CEO Elon Musk announced in ...F150 5.0 P0171 P0174. For the last few months my truck has been throwing an intermittent check engine light due to the same code every time - P0171. The dealer has allegedly checked everything and has given me the "We have done all we can do" speech. Lead tech even suggested that since today's fuels have alcohol in them, that a check …In this article, we’ll discuss the common causes of the P0171 code and provide some valuable tips and tricks to help you troubleshoot and get your Ford F-150 running again. We’ll also provide a table summarizing the …For the Ford F-150 to run efficiently the timing needs to be checked routinely during a tune-up. This will ensure the best performance and gas mileage for the F-150. The procedure ...Welcome to Ford Ranger Forum Thread Tools: Search this Thread #1 11-23-2017, 08:30 PM louisvilleranger95. Ford Motor Co ... Posts: 161 p0171. 1995 4.0 4x4. i am getting a po171 code for lean on bank one. i have changed 02 sensors on both sides fuel filter and pump and had a shop check for vacuum leaks and found none. i have also …Feb 21, 2022 · P0171 is a trouble code that indicates the engine is running lean due to too much air or not enough fuel. Learn how to diagnose and fix this code with FIXD sensor and app, or find a certified shop for professional help. Tools needed for diagnosing advanced P0171 code causes: OBD II scanner or code reader. Carburetor or throttle body cleaner. 1. Disconnected or Leaking Hoses. Air Intake Hose: Find the air intake hose that connects to the engine. Grab and shake it so you can feel if anything is loose.The P1131 code indicates that the heated oxygen sensor contains a failure in the upstream flow. Therefore, Bank 1 is seen as running lean. P1131 is a manufacturer-specific trouble code that is routinely found with several Ford models. The ECM (Engine Control Module) receives data from the oxygen sensors in the vehicle.The most common cause of the P0171 DTC is having an aftermarket intake that is not tuned for. Other common causes include vacuum leaks, exhaust leaks, a clogged fuel system (injector, pump, regulator), or faulty MAF, O2, or fuel pressure sensors. Most often it is an intake or vacuum leak causing the code.P0171 Ststem to Lean. The adaptive fule strategy continously monitors fuel delivery hardware. The test fails when the adaptive fuel tables reach a rich calibrated limit. Possible causes. Fuel system. Excessive fule pressure. Leaking/contaminated fuel injictors. Leaking fuel pressure regulator. Low fuel pressure or running out of fule.P0174 indicates that your Ford F250 is either getting too much air or not enough fuel. A clogged or damaged fuel injector will cause the air-fuel mixture to lean out in one specific cylinder. You may see a cylinder misfire code or fuel injector-specific code with P0174. It’s unlikely that you’ll see P0171 if this is the case.contour98. I've had the CEL on for a while and took it to AutoZone and got the P0171 and P0174 codes. The AutoZone guy says that having both of these codes together (and no others) suggests a bad MAF sensor. With the engine running, he disconnected the MAF sensor then after a few seconds connected it again.Ford p0174 po171 po174 bank f150 lean system too 2001 ranger p0171 codes egr intake source fault windstar valve air P0174 ford f150 code obd p0171 x5 e53 source ...The P0171 code is a generic powertrain code that indicates a lean condition in the engine’s air-fuel mixture. In the context of a Ford Ranger, it specifically points to Bank 1 being too lean. This means that there is either too much air or insufficient fuel getting into the engine on the first bank of cylinders.Aug 12, 2010 ... The P0171 code means it's bank 1, which is the side that has cylinder #1. You could have an exhaust system leak, bad O2 sensor, intake manifold ...Aug 18, 2023 · A 4 Cylinder has only Bank-1. Possible Causes of a Ford P0171 Code: Dirty Air Filter Mass Air Flow Sensor (Codes P0100, P0101, P0102, P0103, P0104) Clogged Fuel Filter Fuel Pressure Regulator... Aug 31, 2023 · The Role of Oxygen Sensors in Identifying P0171 Code. The oxygen sensors are always monitoring how much fuel and air is in the mixture. If there is a vacuum leak, it can cause excess air supply to the engine bay. Then, the O2 sensors will detect a rise in air. Also, broken oxygen sensors can trigger the P0171 code. Modular V10 (6.8l) - P0171, System too lean, bank 2 - Hey folks, my truck is having a problem. I have the service engine light on and the code is: P0171, System too lean, bank 2. The guy at autozone cleared the light and said it probably just needed a good run down the interstate. I didn’t think I would be able to... The most common cause of the P0171 code – and the P0170 and P0173-P0174 codes – is unmetered air entering the combustion system. Most of the time, this happens due to faulty or dirty mass ... P0171 indicates that your Ford Ka is either getting too much air or not enough fuel. A clogged or damaged fuel injector will cause the air-fuel mixture to lean out in one specific cylinder. You may see a cylinder misfire code or fuel injector-specific code with P0171. If you have one or more fuel injectors that have gone bad, that can cause the ...Let's have a look at this 97 Ford F150 with the classic P0171 "Lean Bank 1" code that seems to happens to these Fords more often than not. Typically it is a ...Jul 21, 2023 · Descripción del código P0171 Ford. Este código es un código de diagnóstico de problemas (DTC) que indica que el sistema de inyección de combustible de su vehículo no funciona correctamente, especialmente en la Serie 1. En pocas palabras, significa que el motor no está recibiendo suficiente combustible para la cantidad de aire que está ... Sep 25, 2011 · P0171 And P0174 Essentials. P0171: System Too Lean Bank 1. PCM's Adaptive Fuel Strategy has reached its Rich calibrated limit for bank 1. In plain English, this means that the PCM is adding fuel like crazy to even out the air/fuel mixture because it has detected a vacuum leak in bank 1. The vacuum leak may be real or it may be a “perceived ... Jan 15, 2018 ... Another case of P0171/P0174... · 1. Fuel system clogged/dirty. Check/replace Fuel Filter. · 2. Exhaust Leak. Check for leaks at the exhaust ...HI Everyone: This is a 2001 Ford Expedition with a 4.6 liter engine, no complaints from the customer other than the check engine light is on. This video show...Depending on the engine type, the 2014 Ford F-150 truck has between 302 and 411 horsepower. According to the Ford website, the four engine types include the 3.7-liter four-valve V6...The 1957-1958 Ford Ranchero and Courier pickups were pioneering designs. See pictures and learn about the 1957-1958 Ford Ranchero and Courier. Advertisement The 1957-1958 Ford Ranc...Apr 28, 2022 · The p0171 is an engine code that can be obtained by scanning using an ODBII scanner. It is not necessarily exclusive to the Ford F150 truck and sees use in other models and vehicles. This code represents a problem in the exhaust system and can be connected to the $7E8 Engine Code. The location of this problem usually stems from the fuel trim ... Dec 18, 2019 ... Amazon Affiliate link below https://www.amazon.com/shop/influencer-16c863d5?ref=ac_inf_hm_vp http://www.milwaukeetool.com/ #flatratemaster ...To diagnose the P0171 2010 Ford Fusion code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.Sep 10, 2018 · P0171 indicates that your Ford Ecosport is either getting too much air or not enough fuel. A clogged or damaged fuel injector will cause the air-fuel mixture to lean out in one specific cylinder. You may see a cylinder misfire code or fuel injector-specific code with P0171. If you have one or more fuel injectors that have gone bad, that can ... Sep 10, 2018 · Fuel Injectors. P0171 indicates that your Ford Windstar is either getting too much air or not enough fuel. A clogged or damaged fuel injector will cause the air-fuel mixture to lean out in one specific cylinder. You may see a cylinder misfire code or fuel injector-specific code with P0171. Sep 10, 2018 · P0171 indicates that your Ford Edge is either getting too much air or not enough fuel. A clogged or damaged fuel injector will cause the air-fuel mixture to lean out in one specific cylinder. You may see a cylinder misfire code or fuel injector-specific code with P0171. If you have one or more fuel injectors that have gone bad, that can cause ... Fuel Injectors. P0171 indicates that your Ford Taurus is either getting too much air or not enough fuel. A clogged or damaged fuel injector will cause the air-fuel mixture to lean out in one specific cylinder. You may see a cylinder misfire code or fuel injector-specific code with P0171.One of the most common causes of the P0171 engine code is a fuel system leak. When your fuel system leaks, more air and less fuel will enter the engine's cylinders. This results in your engine running lean because it can't get the necessary amount of fuel. Another problem with the fuel system is clogged fuel injectors.The P0171 trouble code stands for System Too Lean (Bank 1) which means that the vehicle’s computer has detected insufficient fuel flow or increased oxygen flow in the first bank of the engine and both scenarios lead to ”lean condition”. ... Ford: Yes: $100 – $500: Fiat: Yes: $80 – $400: Peugeot: Yes: $100 – $500: What Repairs Can ...Learn what the code P0171 means for Ford vehicles and how to fix it with this helpful video. Expert tips and clear explanations in Spanish.Apr 13, 2019 · The most common causes of P0171 are a bad Oxygen sensor, a vacuum leak, or a dirty MAF sensor. Definition. P0171: Fuel Trim System Lean (Bank 1). Symptoms. Check engine light, decreased fuel economy, misfire, hard to find idle. Common Causes. Dirty MAF sensor, vacuum leak, O2 sensor. P0133, p1131, and p0171. Alright I'm completely stuck. I bought my truck this past summer with the knowledge of a possible fuel pump issue. I replaced the pump assembly and fuel filter along with the plugs and wires and then put some seafoam in and cleaned the maf sensor as well. The previous owner said he replaced the o2 sensor, but …Jun 30, 2022 · Another symptom of P0171 on Ford and other vehicle models is difficulty starting the vehicle. Again, though, it’s worth noting that several factors can cause a hard start. Damaged catalyst converter. If you ignore the P0171 on Chevy or any vehicle model for an extended period, it may damage the catalyst converter. P0171 - System to Lean (Bank 1) The Adaptive Fuel Strategy continuously monitors fuel delivery hardware. The test fails when the adaptive fuel tables reach a rich calibrated limit. For lean and rich DTCs: Fuel system. Excessive fuel pressure. Leaking/contaminated fuel injectors. Leaking fuel pressure regulator.P0171 Ststem to Lean. The adaptive fule strategy continously monitors fuel delivery hardware. The test fails when the adaptive fuel tables reach a rich calibrated limit. Possible causes. Fuel system. Excessive fule pressure. Leaking/contaminated fuel injictors. Leaking fuel pressure regulator. Low fuel pressure or running out of fule.Sep 14, 2023 · Let’s take a quick look at a brief of the P0171 code below. P0171 Definition: System Too Lean (Bank 1) Code type: Generic – P0171 indicates the same problem whether you’re having a Chevy, Ford, or Toyota, etc. Can I drive with the P0171 code? Yes, but you should not drive your vehicle for a long time. Is it easy to fix? Intermediate level. The P0171 code on your Ford vehicle indicates a system too lean condition in bank 1. This means that the engine is receiving too much air and not enough fuel. To diagnose and fix this issue, you should start by inspecting the intake system for any leaks or vacuum hose problems. Additionally, you may need to check the Mass Air Flow (MAF) sensor ... The P0171 error code in a Ford F-150 engine can be a daunting issue to troubleshoot. However, by understanding the various causes of the code, performing a …Meaning. Causes, Symptoms, & Fixes. Causes Identification. Repair Cost. What Does The P0171 Code Mean? Diagnostic trouble code (DTC) P0171 stands for “System Too Lean” (Bank 1). The air-fuel …In this video, I fixed the source of the P0171 code on my 2001 Ford F-150. This code means the O2 sensors detected a lean fuel condition in bank 1 of the eng...May 24, 2014 ... Guest ... Diagnostic Trouble Codes (DTCs) P0171 bank 1 (Cylinder 1) and DTC P0174 bank 2 indicate the fuel/air ratio is too lean. The fuel trim ...The most common cause of the P0171 DTC is having an aftermarket intake that is not tuned for. Other common causes include vacuum leaks, exhaust leaks, a clogged fuel system (injector, pump, regulator), or faulty MAF, O2, or fuel pressure sensors. Most often it is an intake or vacuum leak causing the code.Location: Houghton, MI & Chicagoland. Re: 2002 ford F-150 Code P0171. by Chris's FX4 » Wed Nov 13, 2013 10:52 pm. Try cleaning the MAF first and check the PCV valve itself. Follow the PCV line from the valve on the passenger side valve cover to the back of the intake. There's an elbow back behind the intake up under the firewall, its hard … The most common cause of the P0171 code – and the P0170 and P0173-P0174 codes – is unmetered air entering the combustion system. Most of the time, this happens due to faulty or dirty mass ... Sep 10, 2018 · P0171 indicates that your Ford Expedition is either getting too much air or not enough fuel. A clogged or damaged fuel injector will cause the air-fuel mixture to lean out in one specific cylinder. You may see a cylinder misfire code or fuel injector-specific code with P0171. If you have one or more fuel injectors that have gone bad, that can ... Maintenance Shop - P0171 (Bank 1 lean), P0175 (Bank 2 rich) at sametime - Original problem was running rough and no power with codes P0301, P0306, P0305 & P0306. I changed out the ignition coil, and all plugs, verified wires good. Little to no change, still runs rough. I can pull a plug wire off cylinders 1 through 3...Feb 21, 2022 · P0171 is a trouble code that indicates the engine is running lean due to too much air or not enough fuel. Learn how to diagnose and fix this code with FIXD sensor and app, or find a certified shop for professional help. contour98. I've had the CEL on for a while and took it to AutoZone and got the P0171 and P0174 codes. The AutoZone guy says that having both of these codes together (and no others) suggests a bad MAF sensor. With the engine running, he disconnected the MAF sensor then after a few seconds connected it again.Code P0171 applies to 4-cylinder engines (Bank 1) as they generally have only one bank. If you have a V6 or V8 engine you can also get a P0174 code which refers to Bank 2. When the code says that the fuel system is "too lean," it means that the computer has been adding more and more fuel, which is called Long Term Fuel Trim. | Cnuybxdu (article) | Mcsupent.