4 wire O2 Sensor

mobymidge · Post by **mobymidge** » Thu Dec 23, 2010 7:46 pm

Is there anyone out there have a set of instructions for fitting a 4 wire o2 sensor on a 91 NA6? Currently have stainless extractors with the standard single wire o2 sensor.
Also, can anyone advice on a suitable o2 sensor to install?

Post by **jif** » Thu Dec 23, 2010 10:25 pm

google "miata o2 sensor 4 wire conversion" :]

It'll screw right into the same bung... maybe pick up one from a wreckers to practise on first (wiring-wise)

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SLYDIT · Post by **SLYDIT** » Thu Dec 23, 2010 11:01 pm

you can also use a 3 wire one.
i have a 3 wire in my car.
generally speaking they have two colours of wires. usually they are black and white, two will be the same colour and one different.the two the same are the heater and the third is the o2 signal wire. heater polarity not usually important

mobymidge · Post by **mobymidge** » Sat Dec 25, 2010 5:28 pm

Thanks Jif, now have 4 wire o2 sensor installed. Hardest part was removing the old one.

warrior · Post by **warrior** » Sun Dec 04, 2011 8:32 pm

can I ask where you got your o2 sensor from and how much it was please

mobymidge · Post by **mobymidge** » Sun Dec 04, 2011 9:16 pm

Hi Warrior, I picked one up from Repco. Cost about $150 to $200 (not cheap). I'm going to be upgrading mine again, going to a wideband as I'm replacing the ECU. So will have a 4 wire for sale in a few weeks if you are interested.

warrior · Post by **warrior** » Sun Dec 04, 2011 9:30 pm

I am putting a new exhaust in my car...headers to muffler. I have been told the sensor I have may be to far away in the new headers to work correctly. The exhaust goes in on thursday so will know if I need one buy the weekend. I will let you know, cheers.

SLYDIT · Post by **SLYDIT** » Mon Dec 05, 2011 7:06 pm

if its any further away than the engine/bellhousing join then you will need one.
it might not seem obvious at first but your idle and fuel bill will be bad.

warrior · Post by **warrior** » Mon Dec 19, 2011 9:13 pm

well I was wrong.....after a couple of runs the air/fuel guage started showing RICH all the time so I have purchased a 4 wire O2 sensor.

Can anyone help me fit this as i,m not to sure what to do. I am happy to come to you if you can help me install it?

Angreal · Post by **Angreal** » Thu Jun 28, 2012 2:18 am

I think this is why my car appears to run rich. Just wondering but what's involved in getting an a/f gauge installed as well as a heated o2 sensor? I'm thinking something like this but any advice would be appreciated http://www.innovatemotorsports.com/products/MTXL.php

4 wire O2 Sensor

4 wire O2 Sensor

4 wire O2 Sensor

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