Lexus ES 350 P0174 and P2197?

2007 LEXUS ES 350

155,000 MILES • 3.5L • 2WD • AUTOMATIC

SIXTY6GTO

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I have a Lexus 350 manufactured 01/2007 with the 3.5 Liter 2GR-FE V6........................................... It has the following codes: P0174 (stored) "system Too lean " A/F Lean Bank 2 .................and ....................P2197 (pending) Oxygen (A/F) sensor signal stuck lean Bank two Sensor 1. I used my OBD2 scanner myself.

I want to know what steps to take first. Possibly change out the problematic O2 sensor first? If so, where is Bank two sensor 1? Should I change out all of them given the mileage is high at 155,000 miles?

Mar 1, 2026 at 11:59 AM

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I would not change out the sensors, they are probably fine, unless the heater goes out in them they don't go bad that often. The problem is a vacuum leak or the MAF sensor is bad.

P0174 - System Too Lean Bank 2
P2197 - A/F Sensor Signal Stuck Lean Bank 2 Sensor 1

Here is a video to help find the leak if there is one and this is the location of the MAF sensor so you can swap it out. Cleaning the sensor does not always work, and if it is the problem cleaning it has not worked for me one time FYI.

https://www.youtube.com/watch?v=LRKWV4Are5c

Clear the codes on the repairs have been made. The sensor is on the intake boot. Check out the images (below). Let us know how it goes

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Mar 2, 2026 at 9:08 AM

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