Ok, I've had this error for quite some time and I have read every thread on every Nissan forum pertaining to this error code and I just can't get it to go away. It is the Bank 1 A/F lean. I have done the following so far.

- Replaced the sensor (twice)
- checked for exhaust leaks (fixed one but it was behind the cat so it probably wouldn't have made a difference)
- Replaced spark plugs
- Had the fuel injectors professionally cleaned
- replaced PCV valve
- cleaned EGR valve
- cleaned MAF sensor
- swapped the MAF sensor with one from a working vehicle.
- checked for vacuum leaks
- checked engine ground

It seems that people have done random things like replace all O2 and A/F sensors or replace the Cats and have had success, but those are pretty pricey. Is there anyone out there that can point me in the right direction without having to buy all of this other stuff. The car has 154K miles on it right now.

Thanks.

Scott