ok so after a long process of deleting my egr and fixing exhaust leaks, i finally have sealed the exhaust up. but now i have 2 codes, 21 and 28, which are for both main o2 sensors. I've had these codes before and it would alternate between them and lean afr when my exhaust was leaking.

Do you guys think my 02 sensors are actually bad? which would kinda make sense since its been running rich for a while (2-3 months)

or is there some other possible cause? it never had a code before i started messing with the egr system and exhaust .

It just doesn't make sense to me for them to both go out at the same time.

EDIT: its a soft code btw. it will be off when i go to start my car, and come back on after 10-15 minutes of driving.

and i am currently catless, straight pipe to the oem secondary mufflers. i had gotten 90 degree o2 defoulers but they wont fit on the sub 02 sensor bungs because they are angled. im not sure if this would be a cause as well, but if it was id think it would jsut throw a lean code right?

I did search a lot for people having both codes and didnt find anything, if there is a thread explaning this problem, I apologize. please direct me to it.

 

Unfortunately I have no reply but I am throwing the same 2 codes. (Soft) just like you. Have u solved the problem yet?

 

No I haven't fixed it yet. But I did get the diagnostic chart that tells me step by step what to do. I'll post it on here. But as for me, I believe it's the ecu for sure. I'm gonna buy one with my first paycheck. Then if I get the same codes I'll figure it's something due to wiring. But being I need a new ecu either way, might as well get it first the check everything else after.

 

Thanks for the input tam451. much appreciated. I'll keep that in mind if the codes do come back after I change the ecu.

 

you say soft, buts its actually normal. o2 works when motor is hot... check the grounds and power wires on those 2 sensors.

 

Wow. I just realized this is not my thread. Lol. I posted a code 14 and 22 and for some reason I thought stretchp2 was talking to me. I feel retarded.