# converting to a 4 wires O2 sensor? possible? **URL:** \ **Category:** Integra Help\ **Created:** [July 31, 2002, 4:53pm UTC](https://forum.g2ic.com/t/converting-to-a-4-wires-o2-sensor-possible/26369 "2002-07-31T16:53:48Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Answer](https://forum.g2ic.com/user_avatar/forum.g2ic.com/answer/32/28_2.png) [@Answer](https://forum.g2ic.com/u/Answer)\ **Post date:** [July 31, 2002, 4:53pm UTC](https://forum.g2ic.com/t/converting-to-a-4-wires-o2-sensor-possible/26369/1 "2002-07-31T16:53:48Z")
I have a 90 with header with a one wire O2 sensor and since I have a header, the O2 sensor is located in the downpipe, near the cat. I heard that the 92-93 had a 4 wires O2 sensor because the sensor is far from the engine and thus needed the heater to assure they are at the good temp to send optimal readings. Could I convert my one wire to a 4 wire sensor? why 4 wires? I know one is for the signal, 2 for the heater, but what does the 4th one? Knowing what are doing the 4 wires, I could probably rig something up to control the heater… maybe this would help my bad gas mileage and bad idle. Any help appreciated! ---
**Author:** ![system](https://forum.g2ic.com/user_avatar/forum.g2ic.com/system/32/1_2.png) [@system](https://forum.g2ic.com/u/system)\ **Post date:** [July 31, 2002, 5:27pm UTC](https://forum.g2ic.com/t/converting-to-a-4-wires-o2-sensor-possible/26369/2 "2002-07-31T17:27:53Z")
1 is the signal ( 100mv-900mv) 2 is signal grd 3 is heater power 4 is heater ground ---
**Author:** ![Answer](https://forum.g2ic.com/user_avatar/forum.g2ic.com/answer/32/28_2.png) [@Answer](https://forum.g2ic.com/u/Answer)\ **Post date:** [July 31, 2002, 5:50pm UTC](https://forum.g2ic.com/t/converting-to-a-4-wires-o2-sensor-possible/26369/3 "2002-07-31T17:50:11Z")
nice… Now, is the heater always ‘heating’? Meaning I could screw a 4 wires O2 sensor into my donwpipe and connect the heater to a ‘hot when running’ accessory and i’ll be good to go? ---
**Author:** ![Answer](https://forum.g2ic.com/user_avatar/forum.g2ic.com/answer/32/28_2.png) [@Answer](https://forum.g2ic.com/u/Answer)\ **Post date:** [July 31, 2002, 6:04pm UTC](https://forum.g2ic.com/t/converting-to-a-4-wires-o2-sensor-possible/26369/4 "2002-07-31T18:04:06Z")
Just found the answer! I found a website where a guy retrofitted a 4 wire O2 sensor into his miata… he simply connected the heater wires to a ‘hot when running’ accessory! I’ll go ahead and try it! ---
**Author:** ![system](https://forum.g2ic.com/user_avatar/forum.g2ic.com/system/32/1_2.png) [@system](https://forum.g2ic.com/u/system)\ **Post date:** [July 31, 2002, 9:34pm UTC](https://forum.g2ic.com/t/converting-to-a-4-wires-o2-sensor-possible/26369/5 "2002-07-31T21:34:08Z")
sorry so slow on the reply but, i was gonna say it is on when the eng. is runnin… good luck