Running Oxygen sensor

[jspec civic]

Hi guys,

Is it safe/better to have the O2 sensor connected and running?

If not connected or not working, does this affect tunning or performance?

thanks

[twing]

When there is no O2 sensor, the ECU will run in open loop ... which tends to run very rich.
read more about closed/open loop here:
http://www.hondata.com/techclosed.html

[jspec civic]

i have notice my car is running abit rich..

[tayl51601]

The O2 sensor gives you better fuel economy, without it your call will be very heavy on fuel.

[jspec civic]

Off topic..a warning light is turned on my dash. The exhaust man said that my O2 sensor might not be earthed or something like that..can anyone they what is warning light is telling me?

[beeza]

You need to do an ECU check and see if you get any codes:

http://www.ozhonda.com/forum/showthread.php?t=67113&highlight=ECU+check

You should have your 02 sensor connected so the ECU can get reading.The older the 02 sensor the less accurate the reading.So if it's 100,000km old,replace it.But it may need replacing too if the car is say hesitating/surging,like mine was.

[anjin]

To give you some ides of the effect, I installed after market cams and headers and a vafc, and my primary O2 sensor decided not to work just before tuning. With those cams I expected to have to add fuel. But with the ecu running in default mode due to the O2 sensor not returning a signal the tuner had to dial in 18% less fuel above 6000 rpm. So yes it will run very rich and kill your mileage.

When I fix the o2 sensor it's straight back to the tuner at idle speeds.

[JDM.Power]

top thread guys, just what i needed, im running no o2 sensor atm, i disable it from the ecu.
but it looks like il be needing the o2 sensor, i think im running really rich atm.

[jspec civic]

just relise its my secondary O2 (obd2) thats giving me the heat warning..this warning was on car ever since my conversion. The sensor is bent abit is this the cause?

[~Sp33~]

Off topic..a warning light is turned on my dash. The exhaust man said that my O2 sensor might not be earthed or something like that..can anyone they what is warning light is telling me?

If you have the 02 sensor in and wired correctly yet it's still tripping the code then it's either faulty or it's telling you that your car is running rich and fouling the sensor.

I replaced mine thinking the sensor is faulty, that got rid of it for a while, before the new sensor also fouled. Turned out to be a vacuum leak at my map sensor.

[dumped echo]

In terms of tuning, a lot of tuners will run your new map in open loop anyway. Depending on the computer you may not need your o2 sensor. In terms of a standard ecu, you will need the 02 sensor functioning properly for it to run properly.

On another note you can run a resistor in place of the 02 sensor to trick the ecu into thinking the o2 sensor is there when it isn't.