I have 04 evo 8 with o2 sensor problem. I have had it tuned twice once by dynaflash which when i got my ecu back in the mail it started throwing a CEL for no/low voltage to bank 1 o2 sensor, changed the 02 sensor out with a brand new one from the dealership, did not fix the problem. Had a friend with a laptop remove the map that was on the ECU, he put his on map with my immobilizer code, at which the car would not run, he put my old map back on and it fixed the problem. later on i had a bunch of new parts installed (meth,cams,and etc..) and had it re-tuned by a local tuner, and now that same problem is happening again. the tuner said he tried what my friend tried and it didn't work. also bought another $300 o2 sensor from the dealership, and still the same problem any help would be great!

 

Whats the exact code #

 

Ever splice into your ECU wiring harness? If so you could have the issue right there.

Bust open the glove box and make sure there aren't any loose wires.

 

will do this weekend, hope to find something easy to fix, thanks

 

i'll have to get the # from my tuner