When to replace o2 sensor on S13

[SkylineDriven]

I have a 1993 240SX 5spd with approximately 78k miles on it. When do I need to replace the o2 sensor?

The car seems ok but on occasion the idle is a little funny. It will drop down like it will stall then bounce back up again. Plugs are new, as are plug wires.

[Rockenreno]

the idle thing is fairly common. My car does it. My roomate's car did it until he ran seafoam through the fuel tank. I would suggest changing the O2 sensor if you're getting crappy fuel economy, otherwise I would think its fine.

[Q45tech]

Single wire O2 have a 60k average life, heated 2/3 wire can go 100-120k.............you have to measure the cross counts per minute/second.......switching time between rich/lean..........the faster the O2 switches the more precise the AF is held close to 14.7.

As they become contaminated the switching time slows down, and down , and down.The dynamic range [block learn] is +-20% maximum on closed loop so cruise mpg could change [drop] a max of 20% before the CEL/MIL comes on..............every engine is slightly different.

[DbD]

[

Or, is it, hmmmm I ain't got no bucks right now so the old O2will hafta doo. :help

Thanks. RAP

I would say just go to the local parts store and buy a new one for $19 and have piece of mind. If that doesn't solve your problem, then, heyit was only $19 and was going to be needed in a few thousand miles anyways!

[SkylineDriven]

I'll prolly just go ahead and do it... I might just goto the dealer instead and have them do it for me. Can't be that much right? I don't want to do it myself and then screw up somehow. I'm not that great with stuff like that.

[SkylineDriven]

Ok I found the sensor through the Nissan Parts place on the left... the cheapest O2 sensor was like 26 bucks. Bosch sensor with OE connector. They had other ones but I guess I don't need to get a 50 or 60 dollar sensor if the 26 dollar one works the same.... so now for the mechanical question.... HOW do I install it? Can anyone direct me to a website or maybe someone here could do a writeup on how to replace the O2 sensor, complete with color pictures? That would be most helpful cuz I'm NOT a money bags, so if its that easy I might as well do it myself. I just need some direction thats all.