rx-7fc

i have a air/fuel ratio gauge and i put and i think it works ok with the stock O2 sensor but i have this 3wire O2 sensor and wanted to know how to put it in and should put in

Cameljoe

hook your guage to the signal wire from the O2. I'm guessing it would be the wire thats not red or black.

NZConvertible

3-wire O2 sensors have an electric heater built into them so they start working quicker. This is normally controlled by the ECU as it's not required once it's up to temp. Two wires will be power and earth for the heater, the third will be the signal. There's really no need for you to install this, it's just an emissions control feature.

rx-7fc

i did that but i have a 3 wire O2 sensor not in the car yet but wanted to know how to put it in and if it is better than the 1 wire stock O2 sensor

Chris Ng

most 3 wire sensors have 2 white wires and 1 grey or black wire.. the white wires are your ground and +12V for the sensor heater.. the black/grey wire is the signal line.. run 1 of the white wires to a good ground point, run the other white line (Doesn't matter which white wire) to a SWITCHED +12V line.. The black/gey wire splices into the signal line that goes back to your ECU (has a green connector on it)

O2 sensors need to be at the right temperature (about 600 degrees) in order to read correctly.. a single wire o2 sensor takes awhile to reach proper temperature from the exhaust gas.. it is also possible for the sensor to drop temps in situations of idling, low load etc...

a 3 wire guage will reach operating temps quickly (within 45 seconds) and will also maintain the proper temperature in any situation for correct readings...

All that being said, the o2 sensor really only comes into play when you are in closed loop mode and are cruising. a single wire sensor will work just as well as a 3 wire sensor in 90% of situations..

Also be aware: make sure that the sensor you have is a 0-1v sensor (99% of them are) .. the 3 wire sensor I got with my greddy air/fuel guage was a 0-5V sensor .. you don't want to be putting 5V's into your ecu

rx-7fc

the wires on my sensor are red,black,white

RETed

I wouldn't trust ANY fine readings off these O2 sensors.&nbsp I use them to tell if if the engine is running RICH or LEAN.&nbsp I would not rely on them for any fine readings in between...



-Ted

rx-7fc

is there any good O2 sensors i can buy that will give me good readings the only one i know is a wideband O2 sensor but i don't know anything about them and how to put them in and what i will need

rx7_turbo2

A true wide band O2 sensor is the best but they are not cheap as far as I know. Other than that I think most aftermarket replacements are about the same, I put in a Bosch.

RETed

A wide-band set-up will cost close to a $1,000.&nbsp A REAL wide-band UEGO cost $1,000 just for the damn sensor!&nbsp There have been a number of "economical" wide-band systems that range from several hundred (i.e. FJO) to closer to a grand (i.e. Autronics).&nbsp Other than that, your best bet would probably be the GReddy AFR, which is like $300-$400 and uses the lean-burn NTK O2 sensor.



-Ted

rx-7fc

thanks for all of your help i might just buy a greddy one and the O2 sensor right now i have a auto meter gauge but a lot of people say they are no good or should i stay with the auto meter

rx7_turbo2

Autometer is not the best. They are cheap for a reason. With that said if your on a budget then the Autometer gauge does give you a rough idea of the ratio. It's impossible to gain any type of pin point accuracy with the Autometer. It has alot of pretty lights but all you really look at is if on a full boost run the little lights stay well in the green area.

rx-7fc

i don't have a turbo i have a na and where can i find the greddy afr

rx-7fc

or i don't need the greddy afr because i don't have turbo