Im so lost. i have a custom dual magnaflow exhaust without touching the cats, and a EVo intake, had already replaced my o2 sensors, but still got the codes p1128 p1130 and p1132 back after using the obII sensor. MEchanics have told me its the mass airflow or vacuum leaks, but others told me it was back pressure from the exhaust. i've tried using mass airflow cleaner, and it still didn't work. Any advice!! thanks

 

oh its a 2006 2.7 L boxster

 

P1128 is 'Upstream Heated 02 sensors swapped'
P1130 is 'Lack of H02S Switch. Adaptive fuel at limit'
P1132 is 'Lack of H02S Switch. Sensor indicates Rich'

Did the codes appear shortly after the exhaust and intake was installed?

 

Any clue on how i can fix those problems. I have replaced o2 sensors already so i don't know what else to do. Thanks

 

I think the culprit has to do with the first code, 'Upstream heated 02 sensors swapped'. It's possible the shop that did your exhaust install inadvertently swapped the primary sensors. Try switching their positions, clear the codes and see if they return. I'm guessing it's the first code that is actually triggering the other two.