I recently had my check engine light come on about a month ago for a code p0133 and p0153 so i replaced both number one o2 sensor on each bank. This seemend to fix the problem, but just yesturday i got the same 2 codes again. And i have checked the wiring and its all in good condition. and my air/fuel gauge is constintly on lean, and every now and again its stays on rich . can anyone please give me another opinion on why this problem keeps coming up.

how does the car drive, is it smooth or does it show indication that theres a problem??

it does have problems idling , and it seems to miss when i get moving

the problem seems to be getting worse today it now allmost wants to cut off when i come to a stop... and it feels like the motor has a real bad miss...any sugestions or should i just replace the o2's again

If its gettin really serious then take it to the dealership and find out exactly what is wrong with it. Mine comes one and goes away by itself sometimes.... supposely there is a cat thats a bit clogged doesn't bother me because cars running fine. When the engine light starts flashing then there is something wrong, but if you don't notice anything serious then don't worry about. But it seems like you are noticing stuff so go see a dealership or mechanic shop.

thanks vicls for the response ...but i dont have the money for a mechanic and i wouldn't wanna pay them for somethn i can do myself, i was just curious if someone may have had a problem like this before so i can quickly diagnose the problem. i also have no cats they have been deleted and im running MIL Eliminators for the back o2's so i wont get a light. Im not sure if that would be causing any of this or not but im just tryn to give as much info as possible, so i can fix this on going problem

How you elminate your cats?

V8 or V6?

V8

Is o2 sensor #1 considered the front sensor and #2 the back? I know bank 1 is passenger side and bank 2 is driver side.

I have to replace #2 and I've seen a bunch of replacement sensors online but they are worded front and rear. Or they are worded downstream and upstream.

Is o2 sensor #1 considered the front sensor and #2 the back? I know bank 1 is passenger side and bank 2 is driver side.

I have to replace #2 and I've seen a bunch of replacement sensors online but they are worded front and rear. Or they are worded downstream and upstream.

Nevermind found this post.

http://www.lincolnvscadillac.com/showthread.php?t=34155&highlight=bank+2

Nevermind found this post.

http://www.lincolnvscadillac.com/showthread.php?t=34155&highlight=bank+2

I take that back. I still have a question about the way the parts dealers are wording their parts. What do they mean by upstream and downstream.

Team Ford seems to keep it plain and simple and say front and back.

Upstream is before the cat. Downstream is after.

Upstream is before the cat. Downstream is after.

Thanks NYC