Hello, I got an impreza STI type R v5 with an apexi power FC.
car was tunned 3 years ago, and car going great.
one month ago I noticed a engine check light when I was boosting over 0.9 bar around 5500 rpm while knock reading doesn't go over 20%
any idea ?

could someone check my sensor readings ?





I think first one is engine off and second one is at iddle

 

the only thing I could see but could be wrong is the O2s voltage looks high. My understanding at the O2 voltage should go up and down while idling, go up to around .9v at full throttle and when you lift off it should return to 0v.

unless it's a wideband sensor then the voltage may go higher

 

Lambda does look high, mine usually cycles between 0.3v ~ 0.8v.

 

Very true,

I would be surprise to find a wideband. I guess there is a shortcut or sensor is gone.
I'll check it out

thanks

 

BTW, which O2 sensor is displayed in PFC ?
the one in header or the one in downpipe ?