I need some help, Engine Lean Code 172

[twistedindy1]

Okay, so hear is the deal. I have a 94 ATX with 3.2L. I clear the codes and drive the car until it warms up and again the CEL come on. Setting the same code each time, 172, engine running lean on bank 1. I have checked for vaccum leaks and found none. Both O2 sensors were replaced with the year, but since under warranty, replaced them again and still setting the code. On the highway it seems like going up hills it is fine, no light, but then when comes back down the hill the light comes back on.

Any help would be great.

 

[ohfosho]

partly clogged injector(s) maybe? fuel filter ever done? check the easy stuff first.

what brand O2 sensor are you using, and was there no codes for a bit just after you put the new ones in?

 

[twistedindy1]

I have the bosch O2's and there were not codes ever since I replaced them until now. I ran injector cleaner through it and the fuel filter was replaced about a year ago, but that is cheap and I might just replace it again quick since it is easy to do.