99 silverado with a 5.3 and 80k miles. Just bought the truck and it threw a SES light. Ran the code and it said the right bank was lean or something like that. Ive heard this can be a fuel filter or maybe o2 sensors. I will be replacing the filter but I dont want to replace all the o2s unless I have to. Is there any way to test them to see if they are the problem?

 

replace the bank 2 sensor 2 o2 sensor.... post cat pass side...

 

how do you know that?

 

What was the code number?

 

Could swap the left with the right... if code follows, badda bing, badda boom! If not, look at the front sensor. Can't say for sure without knowing the P-code?

 

I didnt scan it myself...I knew I should have gotten the code! Knowing the exact code would tell me what sensor it is?

 

I had the same problem myself. Bank 2 sensor 2 showed lean condition.
Front o2 sensor monitors engine and rear o2 monitors cat performance. I too suspected a bad o2 sensor so I took it to a friends garage and he pointed an infrared temp gun at it and it showed a difference of 100* cat discharge temperature behind bank 2 as compared to bank 1. He said the cat. wasn't working properly. I contacted Dynatech and after explaining the problem they did (reluctantly) send me a replacement cat at no charge. Problem solved.

 

It seems most people always want to replace a sensor. There's a very good chance the sensor is fine and doing what it was designed to do...tell you your cat is malfunctioning. Swap the passenger side with drivers side O2 and see if you get the same code. If you do, the sensor is telling you what is wrong.

 

b/c my truck was doing the same thing, replaced intake gaskets, and there is a buletin about it.... the o2 sensor causing the problem

 

...which is why knowing the trouble code is important. Not knowing the code, I suggested swapping the sensor. If problem followed, then you have the issue. If not, then problem lies in the emissions.

Always post the codes. Makes helping easier.