Oct 10, 2018 · P0171 Definition The P0171 code means that, on the first bank of the engine, the fuel system is running weak (or lean) or a vacuum leak exists near this side of the engine. A …

Jan 5, 2013 · RX - 2nd Gen (2004-2009) - FINALLY SOLVED! P0171 and P0174 Codes!!!! - P0171 and P0174 I know this is long, but if you've had these codes, please read the entire …

Nov 19, 2018 · Code P0171 applies to Bank 1 and P0174 applies to Bank 2. Code P0174 mainly applies to V6 or V8 engines because 4-cylinder engines generally have only one bank, though …

Feb 12, 2018 · LS - 1st and 2nd Gen (1990-2000) - 98 Lexus LS 400 p0171 and cannot figure out fix - I have a 98 Lexus LS400 with the p0171 code. I have replaced the MAF sensor, all o2 …

Jan 4, 2010 · RX - 1st Gen (1999-2003) - error codes p0171 ,p0300,p0301,p0302,p0303 - check engine light popped on these codes came up ;P0171, followed by pending codes p0300 ...

Jan 30, 2012 · A technical documentation that outlines diagnostic trouble codes (DTC) related to fuel system imbalances in vehicles, specifically for 'System too Lean' or 'System too Rich' …

Dec 4, 2025 · IS F (2008-2014) - Lexus IS F forum discussion, how-to guides, and technical help.

Mar 23, 2018 · If you read through the many dozens of P0171 threads on various Toyota/Lexus forums, you will find the solution is almost always a dirty MAF sensor. No one knows why the …

Dec 20, 2001 · ES - 1st to 4th Gen (1990-2006) - Forum discussion, how-to guides, and technical help for the Lexus ES300, ES330, and ES250.

Dec 7, 2025 · IS - 3rd Gen (2014-present) - Third-generation Lexus IS forum discussion, how-to guides, and technical help.