so my CEL came on. so i check for codes. i got a 04 09 code, and then i turned the light off. i went to the ECU decoder website at vbxmaxima.com or whatever it is, and that told me that it was UNDEFINED. WTF? does anybody know what this code means? thanks.

 

front o2 sensor bank 1....i have teh FSM in front of me

 

i was thinkin it was prolly an o2 sensor. why didnt that stupid decoder thing tell me that? also, i reset the light, but it will prolly come back on right?

 

yeah, it'll come back eventually.

 

that is the sensor in the bank closest to the REAR of the car, right? or is it the sensor closest to the FRONT of the car???