Hey all i'm ditching the whole smog thing and i heard that with the FI comp if the i still have the O2 sensors hooked up but not taking exhaust readings that mjy car wont run right at all. Is there any truth to this? and if so does anyone know a way to remove the whole wiring and stuff for the O2 sensors or should i just cut them right off from the exposed wiring? thanks

Yes. You need O2 sensors for the EFI to work correctly.

The 02 sensor is not part of the Smog emmissons system, its part of the engine tuning system and is an integral part of the engine system. Remobing the O@ sensor would be like removing the air flow sensor. Your car would work, but not very well.

so i cant remove the 02 sensors or the car wont run right...well then ill have to think of something cuz my new exhaust wont have a place for those sensors and neither will my header...there must be a way around it or ill just have to waste 2k on a triple carb conversion or something thanks for your help

You can buy headers with a socket welded in for the O2 sensor.

Wouldnt the whole efi system run wrong if i took the 02 sensor that was after the catalytic convertor and placed it at the head? Cuz then wouldnt it make wrong adjustments since it would be reading the uncatted emissions?

P.S. i've ran my z without the 02 sensor plugged into anything and it seems to run the same as before so i dunno ill just have to see how it runs when i get the whole new exhaust system if its really bad i think ill make my own space for it to screw in on the exhaust pipe thanks again

Originally posted by 280zgod

Wouldnt the whole efi system run wrong if i took the 02 sensor that was after the catalytic convertor and placed it at the head?

I might be wrong here but if the O2 sensor is after the cat then it IS in the wrong place. You would want the sensor close to the collector on your header to get an accurate reading.

you can get any exhaust shop to install a oxygen sensor for a small price

to have the flange welded in that is,

without a O2 sensor, the car will run extremly rich on idle, and you will notic how much it drinks

alright then so it is needed no matter what. well thats no biggie then rather then take it to a machine shop ill do it myself its just welding a nut into a pipe pretty much. besides my parts havent even come yet i have my z sitting in the garage exhaustless all the way to the head. while im on the subject of parts anyone know of a performance comp or anything to boost the efi system cuz 70's technology seems a bit shaky to me. thanks again for the help

well i got the parts and installed them myself and tested the car to see how it ran with the 02 sensor out and it idles at 2000 rpm or it dies and it has almost no power(extremely slow accel and gears have lost 20 miles per hour each) so hopefully getting the 02 sensor put in the system will make it work right i dunno though

Where is that O2 sensor supposed to be at? My 78 280Z has a header on it.

Originally posted by TomoHawk

Where is that O2 sensor supposed to be at? My 78 280Z has a header on it.

According to the FI video I just watched this week by Kim Blough, there isn't an O2 sensor on the '78 280Z - there wasn't an O2 sensor until the ZX.

Good. 1 less rusted connector to worry about.