[Gizm0]

Unplug your primary O2 sensors and see if the misfire persists... if the car runs "fine" in open loop, then it's most likely O2 sensor related... where did you buy your bosh sensors from? I've got some bad ones from a reputable source before...

Also, secondary O2 sensors are often overlooked... secondary O2 are narrow band and used to fine tune the AFRs under low load/idle for ideal AFRs. From my understanding, primary and secondary O2 work together, the secondaries are not used to only monitor the converter's health but contribute to ensure ideal AFRs

[Jason2130]

On my n54 I got constant misfire on cylinder 3 while car idle but it drive fine and make boost I did a compression it was good, swap coils and plugs swap injectors also walnut blast, put in multiple msd81 still come back has any had this problem