no o2 sensor?

[coolcloo1019]

I was talking with a KA owner yesterday and was told that some KA's run better with no o2 sensor. His isn't hooked up and its running fine. Has anyone else heard of this? Thanks.

[nissilvat]

ise he using a wideband o2 sensor then?, it just seems w/ no sensor, the car would run too rich, ya know

[deviousKA]

On sohc 8 bit ecus the self learning capability of the ecu allows it to run without o2 sensor. After a certain amount of starts without the o2 sensor connected, the ecu will kick over into full non closed loop mode. It will then read directly off of the ignition and fueling tables that are stored in the eprom. The stock ecu only reads off of the eprom in open loop, as far as the main fuel/spark tables are concerned. This is handy for ecu tuning. Of course this shouldnt be done without some sort of o2 (wideband) that runs seperately from the main ecu, for tuning purposes.

Dont know if dohc (16 bit) 240sx ecus operate in the same way. You have to manually switch to a tuned rom via an installed daughterboard. Im not sure if closed loop functions are even a problem.

[coolcloo1019]

Yeah, I forgot to mention that he has a ROM tune and emanage e-01. That would definately make a difference. Thanks for the input, i forgot that he had those things.