Please read my 2 post under the form of the GS 2nd generation section by me kyGS400.

1. GS pulling fuel pump...gas spewing....why (posted 11/27/2008)

2. What is code of system too lean bank 1, stated incorrect, I know the code but please read the entire post (posted 11/23/2008)

Thanks for your time,

Charles
mbrooks11@hotmail.com

 

Man, I wish I could help, but that is going to require testing everything in those systems... First off, I hate to say it, but I think Lexus guessed at your problem and said replace the o2 sensors - good chance they didn't have anything to do with the root cause of your problem...

The absolute first thing I would do, based on history, is get someone to check fuel pressure... I have a feeling something happened on the installation of the fuel pump/fuel filter... Is the p0171 the only code in the system???