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VN V8 O2 sensor
Posted: Fri Jul 19, 2013 6:10 pm
by eckermannk
Hi,
I have a VN V8 in my Torana and just connected ECU with the NVRAM and and Tuner Pro. I am getting O2 readings at idle around the 400mV to 450mV. Once the car warns up and give it a couple revs it ranges from 120mV (yellow) to 800mv (blue). Now im guessing this it not good??? I have replaced the O2 sensor with another and it behaves the same way.
Im not sure where to go from here. Could it be a sticky/faulty injector? Is there any issues or symptoms that cause this the O2 to behave this way?
Any help is appreciated.
Re: VN V8 O2 sensor
Posted: Fri Jul 19, 2013 6:33 pm
by VL400
During closed loop it will swing rich (above 450mV) and lean (below 450mV).
Take a log and post it up, can then check if its doing what it should.
Re: VN V8 O2 sensor
Posted: Fri Jul 19, 2013 6:53 pm
by eckermannk
Hey,
I noticed the closed and open loop. Still learning as you know. Attached a log. Let me know if you see anything else out of the ordinary
Re: VN V8 O2 sensor
Posted: Sat Jul 20, 2013 10:18 am
by Holden202T
it looks like its definitely working, i'd suggest you really need to go for a drive and log that to see if its doing what it should, you probably can't get it up to temp properly idling.
Re: VN V8 O2 sensor
Posted: Sat Jul 20, 2013 10:28 am
by eckermannk
When I seen it run into the yellow I thought is was running lean. Just wasn't sure if it was another issue causing it to get them readings.
Talking about proper temp. I have AU thermos installed. At what temp should I set them to kick in? I have them a 92 deg and added 3 IAC steps when they kick in. Does that sound about right?
I want to take it for a drive.

But I dont register the car over winter. I have to wait till September.
Re: VN V8 O2 sensor
Posted: Sat Jul 20, 2013 11:02 am
by Holden202T
well my theory with the fans is if you have a 80 degree thermostat set the fans for 85 ....
even if you can't drive it maybe put it up on stands and use the brakes to load it up and bit to simulate road driving, you want to probably get it at 2000-2500rpm and like 40-60kpa and see if the o2 starts working as it should ... if you do it though make sure the motor is up to running temp.
Re: VN V8 O2 sensor
Posted: Tue Jul 23, 2013 6:06 pm
by eckermannk
Well i took it for test run around the back streets.
A couple things I noticed is that the O2 Sensor is still all over the place. Not sure if this is normal?
Should the road speed closely reflect the speed im traveling. Well I wasn't traveling at 45kmh and hour. I have a module that screws onto the side of the speedo outlet on the trans. This sends the signal to the ECU and the speedo cable also plugs into it so i can use my dash. Its a 4 pulse sender. I guessing its not enough?
I don't really get on till around the 7:30 and 10:00 mark.
Any help is appreciated
Re: VN V8 O2 sensor
Posted: Tue Jul 23, 2013 6:15 pm
by eckermannk
I just found the Parameter "Speed sensor constant Pulses/Kilometer" Its set at 6248.14 PPK. Thats a little high for the 4 pulse I have. Should I try and change this to match true road speed?
Re: VN V8 O2 sensor
Posted: Tue Jul 23, 2013 6:19 pm
by VL400
The O2 sensor looks healthy. At 3:37 its in closed loop and getting heaps of cross counts. When your not in closed loop at 4:03 and target AFR is rich due to load it goes to ~850mV which is normal.
The road speed can be spot on, but does need to be setup using "Road speed params - Speed sensor constant Pulses/Kilometer".
To work out the PPK (pulse per kilometer) value use PPK = (1000/Circumference in m) * Diff Gear Ratio * Pulse Per Rev Of Sender
Re: VN V8 O2 sensor
Posted: Tue Jul 23, 2013 7:06 pm
by eckermannk
Cool, Thanks VL400 for your input.
I also have noticed the knock detected is "SET" and recording knock counts in the items list. I'm not getting any knock retard values. I don't have a knock sensor. Should i turn this off or just leave it. If so, what parameters turn it off.