P0174 code mercedes. Hey, folks. A P0174 code indicates a lean condition on bank 2, often caused by vacuum leaks, faulty oxygen sensors, or mass airflow sensor issues. . 7K views 2 replies 2 participants last post by Check Codes Mar 21, 2013 D P0171 & P0174 BANK 1 & 2 RUNING LEAN WHAT DOES THIS MEAN AND WHAT REPAIRS ARE NEEDED. Why this has never been posted here I'm not sure (probably that lazy former mod), but here's a series of posts (to get around forum limits) of Mercedes Benz Diagnostic Trouble Codes for MY 1996+. At idle, if you look at the streaming data, the MAF is registering around 4. Find the meaning, symptoms, and the most common causes of the P0174 code - Full professional diagnostic guide. g. 6L Pulled codes a few days ago and showed both bank 1 and bank 2 lean. Could a bad throttlebody gasket cause this? 171 and 174 codes? I recently had my local Mercedes dealer replace the intake manifold and intake gaskets due to a start and immediate shut off situation I would like to think if they would need to remove the throttle body from the manifold theyd put a new gasket in Learn how to diagnose and fix the P0174 error code in your Mercedes-Benz C-Class. c8cf5868. See a P0174 OBD-II code on your dashboard? Learn the causes, symptoms, fixes, costs, and book a mobile mechanic for P0174 diagnosis and repair nationwide. On V6/V8/V10/V12 engines, Bank 2 is the side of the engine that doesn't have cylinder #1. This might come in handy for some people: Mercedes Fault Codes Fault Code Fault Description Area B1000 HRA Headlamp range adjustment: The supply voltage of the control unit is too low (Undervoltage) Body B1004 LCP Lower Control Panel: Control unit does not match vehicle 2006 Mercedes E350 3. Sep 12, 2025 · Is your car showing a P0174 code after scanning your check engine light? This code points to too much air in the engine, causing your car to run lean as opposed to running rich. I've also attached a pdf of the full list to this first post. On my 02 S55 160k miles I've been trying to solve these codes. also replaced one of the two fuel pumps passenger side. Feb 12, 2023 · How to diagnose the P0174 code easily. MAF was replaced two months ago. Repair Information for P0174 code. The p0171 and p0174 only gets set after an extended period of driving and only at an Learn what the P0174 code means, why bank 2 is running lean, common symptoms and causes, how serious it is, and what to check to fix it. The first letter indicates the type of code: P = Powertrain C = Chassis B = Body U = Network P0101 MAF Circuit Range/Performance Technical Description Mass Air Flow (MAF) Circuit Range/Performance What does that mean? This diagnostic trouble code (DTC) is a generic powertrain code, which means that it applies to OBD-II equipped vehicles (Nissan, Chevrolet, GMC, Mercedes, VW, Toyota, Mazda, BMW, Ford, Audi, Honda, etc. Basically this P0174 code means that the upstream oxygen sensor in bank 2 reporting a lean condition (too much oxygen in the exhaust). In this article, we'll explore some of the common issues with the intake manifold I am going through the same P0171 and P0174 codes. - Download P0171 and p0174 codes on my 2005 c240. p0174 Replaced mass air flow sensor replaced vac booster. If the P0174 is set in along with the P0171 code, it is highly likely that the problem is caused by an intake leak. Learn what Fuel Trim System Lean Bank 1 means, location and how to repair. Find the meaning, symptoms, and the most common causes of the P0171 code - Full professional diagnostic guide. Connected scanner and based on diagnostics, seemed MAF was at fault. - Lambda control, before left TWC, Lambda control is at lean stop. I am thinking vacuum leak some where else any There are a few primary causes that can create trouble code P0174 to read on your OBD2 scanner: Learn about P0174 symptoms, causes, and potential solutions from the diagnostic experts at RepairPal. P1234). Codes P2189 and P2187 indicate fuel mixture issues at idle and deceleration, while P0174 and P0171 show lean conditions on both banks. If the P0171 Mercedes-Benz is combined with the P0174 Mercedes-Benz code, it’s very likely that the problem is caused by an intake leak. Here's everything you need to know about the P0174 error code, including how to diagnose and, most importantly, how to repair this issue. OBD II Fault Codes Reference Guide The Diagnostic Trouble Code numbering follows a standardized structure. However, like any complex piece of machinery, these engines are not immune to issues, and one of the areas prone to problems is the intake manifold. Prompt diagnosis is crucial to avoid engine damage. Dec 31, 2025 · The P0174 code indicates a lean fuel condition on bank 2 of the engine, which can lead to poor fuel economy, rough idling, and engine damage. The P0174 code indicates a "System Too Lean" condition in Cylinder Bank 2, meaning the air-fuel mixture is unbalanced, with too much air and not enough fuel. If there are no intake leaks, the next step is to replaced the air filter and clean the air flow meter. 5: Diagnosing P2189, P2187, P0174, P0171 Codes E350 often faces fuel trim imbalance and oxygen sensor failures causing rich or lean conditions. Drove car for awhile and threw another code. Feb 13, 2026 · Learn what the P0174 code means, why bank 2 is running lean, common symptoms and causes, how serious it is, and what to check to fix it. Update had a Smoke test done and they think it’s comin from the throttle body. Came up after I replaced crankshaft position sensor from a previous code. Inspect the intake manifold gasket and vacuum lines for leaks. Finding the root cause of a P0300 code can be a complex puzzle, but understanding the possible causes is key to a successful repair. Common causes include a faulty mass airflow sensor (MAF), vacuum leaks, or malfunctioning fuel injectors. I replaced everything so far except for the injectors. Vacuum leaks, faulty oxygen sensors, clogged fuel injectors, malfunctioning mass airflow sensors, and fuel pump issues can cause the P0174 code. All new parts: vacuum hoses, O2 sensors, Engine seals, spark plugs and wires, MAF and Camshaft and Crankshaft sensor with Bosch parts all replaced within the last 4 months. Troubleshooting the P0174 code requires identifying the root cause of the lean fuel condition on bank 2 to prevent further engine damage. I have been getting the 2 different bank lean codes, P0171 and P0174. Ok I have a puzzler. p0171 and p0174 Tags check engine light code p0174 p0171 w220 Jump to Latest 1. Still having the P0171 and P0174. If the problem persist the front oxygen (O2) sensor may need to be replaced. What about the obd code? I have a 2002 Mercedes E320 with Approx 127k miles on in. How to diagnose the P0171 code easily. Jan 24, 2026 · P0174 means the engine control module has detected that the air-fuel mixture is too lean on Bank 2, indicating too much air or not enough fuel entering the engine. Make: Mercedes-Benz Code: P0174 Definition: Improper/Lean Mixture Formation-System Too Lean (Bank 2) Description: Engine output is affected by: - Self-adaptation of mixture formation for enrichment at partial load or at idle for the left cylinder bank is below the permissible limit. This A P0174 diagnostic trouble code (DTC): System Too Lean (Bank 2) occurs when the engine control module (ECM) or powertrain control module (PCM) detects that the engine is receiving too much oxygen or not enough fuel. All Diagnostic Trouble Codes have a letter followed by a 4-digit number (e. I have a few code scanners that I am using to troubleshoot, one of which is the Carsoft code reader. We detail how to pinpoint the exact cause (air, fuel, or vacuum) and provide actionable repair steps. I have recently been doing repairs myself to help save money and it has been going well. P0174 means System Too Lean (Bank 2). Cause: Self-adaptation mixture Mercedes-Benz has long been synonymous with luxury and performance, and their M272 and M273 engines have played a significant role in delivering on these promises. Although generic, the specific repair steps may vary depending on Every engine part changed, still has P0171 P0174 codes Pt1 How to find a Small EVAP leak without a smoke machine Part 2 EricTheCarGuy Explains Check Engine Codes: P0171 - P0174 Air Fuel Mixture This document contains a list of OBD2 codes for various Mercedes-Benz vehicle systems, providing the code number, system, and a brief definition of each code to indicate what component or system the code is referring to. 1771394020. P0171 P0174 Engine Codes - MAF replaced Jump to Latest 3. Exchanged MAF for new replacement under warranty. The P0174 code means that more air than gasoline is detected in the exhaust gases exiting the combustion chamber. 1830ee0a Every engine part changed, still has P0171 P0174 codes Pt1 Check Engine Light? System Too Lean - Code P0171 or P0174 on Your Car or Truck How to Diagnose Codes P0171 & P0174 - Lean Bank 1 & 2 Troubleshoot your car's P0174 - System Too Lean Bank 2 code: learn the symptoms, causes, and steps to fix the lean fuel mixture issue. Come join the discussion about your R170/R171/R172 SLK, or AMG performance, modifications, troubleshooting, maintenance, and more! 2002 Mercedes c240: p0171. Repair Information for P0171 code. So get your HF code Please contact your administrator with the error code: 0. ). Does anyone have any model specific pointers as to what to look for on a 2010 E350 petrol throwing P0171 & P0174 codes? I am assuming an air leak is the most obvious fault? I can see nothing obvious but it is difficult to look at the back of the engine. There are over 250 codes listed across multiple vehicle systems including oxygen sensors, camshaft positions, fuel delivery components, emissions systems, and more. also replaced one of the two fuel Mechanic's Assistant chat Customer: 2002 Mercedes c240: p0171. Learn what Fuel Trim System Lean Bank 2 means, location and how to repair. These are codes telling you that the engine is running rich. Fix the P0174 “System Too Lean” code. In this article, we’ll explore frequent causes of a P0174 code, how serious it is, and how to fix it before costly repairs are needed down the road. Also includes links to relevant forum topics on the code. Car Today we are talking about why you might be getting a P0171 and or P0175 engine code. 7K views 6 replies 3 participants last post by tim687 Nov 6, 2023 G A forum community dedicated to Mercedes SLK owners and enthusiasts. Repairs Performed so far 1) Replaced MAF 2) Replaced Throttle postion sensor 3) Replaced Fuel Pump. P0174 means System Too Lean (Bank 2). Detailed information on troubleshooting and repairing a P0173 DTC code which refers to a fuel trim malfunction on Bank 2. I have performed the following work with a Big assistance from the DIY procedures found in this forum. 0 grams/second of Air 2004 C240 2. Learn symptoms, common causes, how to diagnose fuel trims, and proven fixes for vacuum leaks, MAF, and fuel issues. yarbrs, 1jvfo, eztos, zqepm, qjdn, w3mq, 6u6nl, 4klle, dkyaz, v9la,