Thread: b14 ser cluster

hi i am new to nissans but have worked on many cars i bought a ser cheap and love it very fun car but i bought it with 2 problems one is the tach on the cluster doesnt work and never has worked for me i have no clue what the issue is i replaced the cluster and still doesnt work some one please help me the other issue i have is the ecu is in tune mode it tells me what the 02 sensor is doing all the time and will not back out of it my check engine light always blinks to the o2 sensor