Hello everybody. I have an '03 Z (52,000 miles) & my "Service Engine Soon" light came on. I hooked up an OBD sensor to my car & the following codes came up:

P0037
P0057

This led me to believe that my bank 1 & bank 2 02 sensors needed to be replaced, so I had them replaced (Bosch sensors). Well what do you know, the same codes popped up again a few hours after I replaced my 02 sensors. Does anybody have a clue what the problem could be, or does anybody know a good shop around San Francisco I could go to? Some of my friends tell me it could be my MAF sensor, but I have no idea at this point. Any advice would help. Thanks.

 

interesting. i had the same issue on my car.

i had bought my car used when all of a sudden it started throwing those codes. it turns out my car had test pipes that the previous owner had installed and his botched install (clipped the wires on my O2 sensor) had caused the code.

You say you already replaced the O2 sensors once and the code came back? is your car running extremely rich? if so then it could be dumping fuel into your cats and that will nuke the cats for sure. I think you have bad catalytic convertors.

my solution- instead of replacing the cats just get test pipes and non foulers and be done with it. increase in horsepower, better sound, and no more CEL light. your inspections might become a little harder but...it would be worth it

 

I bought my car used too. I've only had it for about a month, so it's tough to tell what mods the previous owner might have done.

you really think it's my cats? the car just got smogged a few weeks ago...but I'm no expert...

any brand recommendations for test pipes & non-foulers?

 

i DIY spent 800 dollars because of the CEL back in 04 with my wife's German suv. Changing all four O2 sensors did not eliminate the CEL, replacing the expensive MAF sensor did.

 

i think those are the heater circuit codes. I believe if the o2's are not switching then you would get a P151 code or along those lines anyway. if you already changed the sensors you probably have a wiring issue going to the o2's. Heater circuit isn't working. o2 was probably switching all along and you wasted your money. just a hunch and something to look into, however.

 

Also possible exhaust leak. We have seen many test pipes and/or high flows that were cracked kicking those codes.

 

Good info...
I got P0057, already replaced the O2 sensor and still showing... I just found a crack in the exhaust, but is all the way in the back... Any ideas?