Hi all, i recently removed my secondary cats.. we put back in the (2) O2 sensors (that where with the secondary cats)
i then drove a few miles to the dyno shop to have my Apr software updated, (i also had a new OEM) N75 installed , as i figured it couldn't hurt
the dyno folks sent me this email last night
Thanks John, we installed your new N75 valve no problem andran her up on the dyno… your car is running lean, but itis not the calibration. Something is causing the car to under-fuel, potentiallythe O2 sensors, so we will continue investigating in the morning (car is stillon the dyno).
i have spoke to them today , they are doing some more tests (table readout) or something..any thing i should ask...as a mechanical potato (me) ..i just though someone may know what may cause this?