O2 Voltage Question

[Rekin]

Hello,

Quick question;

- What voltage does the o2 sensor show on idle once warmed? Mine is cycling crazy between 0 and 1v.

- What voltage does the o2 sensor show when cruising at constant rpm? I know it should be cycling between 0 and 1v, but sometimes mine locks up on 0.06v.

Just want to check if my o2 sensor is playing up.

Thanks

[t_revz]

it should be cycling crazy during idle and cruising and only sit still during heavy acceration and decelaration.

[Moodles2]

When cruising at a constant engine load, you'll ideally want to see 0.4v - 0.6v.

I don't know much about O2 sensors, but the fact that it still cycles means it's not completely dead. If it is indeed showing lean mixture @ 0.06v, check how much black smoke it's putting out as the ECU will richen things up to compensate thinking the engine is running lean. If it's blowing lots of black smoke while reporting a low voltage I would be looking at getting a new o2 sensor.

[MrStabby]

Flicking back and forth is good - it means that closed loop is working and therefore that the o2 sensor is working.

Locking during closed loop (light load) means its on its way out, so you might as well replace it now. IIRC workshop manual says replace every 40,000kms but of course there's no need to do that since you can check it.

[V28VX37]

I was looking for the same thing recently and found this great read: Replacing an oxygen sensor on a R34 GTR

This is what Nissan DataScan shows for a stuffed sensor (top graph):

and with a properly functioning O2 sensor:

Note that the GT-R has two sensors but the principle is exactly the same.

R34 owners read this is you don't have access to DataScan: R34 Oxygen Sensor Test, Great 5 Min Test ( GTR not included )

My O2 was stuffed and I got a brand new OEM one from Kudos. I has clearly improved the fuel economy.

[Rekin]

thanks for the info.

It used to cycle during cruising but now it just sits on 0.06v when cruising! Can feel timing being pulled back and car feeling funny. It happened after 18 runs at the drag strip. O2 sensor probably cooked itself haha

I replaced my o2 sensor last year, so its only done maybe a max of 15,000km.

My car also idling at 1000rpm after the drags but I dont think thats related to the o2 sensor...

Guess a new o2 sensor :S

[Moodles2]

Did you use any fuel additives at the drag strip? if so the additive might be the cause of the sensors death

[Rekin]

Did you use any fuel additives at the drag strip? if so the additive might be the cause of the sensors death

nah didnt use any. I'll suss it out on the weekend, will just replace it i guess