Bank 1 and 2 too lean.

[renda10]

I scanned my truck (02 explorer sport) and i got a Bank 1 and 2 too lean code. I was wondering if i had to replave both o2 sensors or just the one?

 

[Nightkil13r]

Have a Shop run a diagnostics test on the engine, they will be able to tell which sensor is bad and replace only that one. There are 4 on the 02 X's with the 4.0 sohc 6 cyl. 2 for each bank, i just had my front bank 1(driver side just ahead of the Cat) O2 sensor. Im not to sure on how much it cost because it was done at the same time as my transmission rebuild. The next project for my X is to replace the Front 2 Cat's

 

[ranger7ltr]

were these stored or pending codes?

My X started running like crap and stored a bank 1 too lean and a downstream O2 sensor not switching... The culprit here was a load of ****ty fuel with water and rust in it.. I just finished draining the damn tank and I am about to change the filter [again] and added fresh fuel to the tank...

I will drop this tank and clean it out myself if I need to do so...Is your truck running properly or is it seemingly starving for fuel or not accelerating as quickly as normal?

 

[jlsparky7]

My X started running like crap and stored a bank 1 too lean and a downstream O2 sensor not switching... The culprit here was a load of ****ty fuel with water and rust in it.. I just finished draining the damn tank and I am about to change the filter [again] and added fresh fuel to the tank...

I will drop this tank and clean it out myself if I need to do so...Is your truck running properly or is it seemingly starving for fuel or not accelerating as quickly as normal?

+1. Dirty gas and clogged fuel filter.

 

[aldive]

More than likely the O2 sensors are not bad; look upstream for the problem.

Good luck ...

 

[HahnsB2]

Replacing the O2 sensors is like shooting the messenger, they are reporting a problem.
I would put my money on a vacuum leak.