pulled koeo codes 172 556 need a thought on them
 

I pulled the KOEO codes and got 172 and 556 which are supposed to be O2 sensor on right side lean andfuel pump circiut failure respectively, what does this tell me I need to dol to fix the problems? do I need an O2 sensor and fuel pump? the car runs fine, but the CEL flashes at me sometimes. could the right side being lean be because of something else like injectors?

I guess noone has any input on these, thanks for looking anyway. I have tried to search out the answers and . . . no luck. I think I will try changing the right side o2 first and see what happens

p0172 is a bank 1 running rich code. p0171 is a lean code. if your running rich do you have any access to a decent scanner? it might not be a sensor. the sensor could be right and that you are really running rich. check your MAF sensor for any dirt on the hot wire. if so use a little electrical cleaner or rubbing alcohol with a cotton swab lightly. thats all i can think atm ill get back if i think of anything else. good luck

thank you I will go clean the maf now and see if that helps. My fault on the code 172, what I have says lean but I am new to this so I could be wrong.

cleaned MAF hot wire and ran car up to temp then reran codes.....111 111 thanks for your help . And no engine light