What happens when O2 sensor goes ta ta's

[Doctor]

Anyone shed some light on this issue?

Thanks in advance,

Doc

[DKS1DR]

When O2 sensor goes, it takes fuel economy with it.

[Doctor]

Does it effect idleing etc

[darkhalf]

i dont think the ECU goes into close loop (ie uses o2 sensor) during idling

from the doccos i've read for the RB30 ECCS, only above 2500rpm and only at crusing speed. the lights on the ECCS start to flash lean/rich/okay/dead when in closeloop. the RB20 eccs should work similarly from what i've seen

[initialD]

when i had my HD clutch installed they accidently damaged my 02 sensor, i'm assuming this is the 02 sensor every1's talking about.

the 1 thats hard to reach!

nyways at idling, it wud drop in revs all the way down to 0, till the car almost stalls, then it wud bounce up and down from 0 to 1,000 rpm

[WazR32GTSt]

where is the O2 sensor, and how do you clean it?

[darkhalf]

i've read somewhere you can 'clean' with high temperature like a butane torch or something.... dunno if that would work. o2 sensors have a limited life span and if they rattle they are dead (small chemical plate inside has broken)

if a car is hunting at idling then i dont think its the o2 sensor, but the Auxillary Air Control valve maybe instead (you can disconnect this to see if there is any difference)

[lowlux]

is there a way to find out to see if its dead? cause i think mine might be farked

[darkhalf]

yeah there are several ways...

find the wire for the O2 sensor going to your ECU and put a + probe from multimeter on it. put the - probe to the chasis and drive your car. it should vary between 0-1volts. if it stays at 0v its dead

or you can use an Air Fuel meter (various kit forms from Jaycar) and if its 0 then its dead

on the RB30 ECCS if you have the car warm temp, running @ ~2500rpm (no throttle switch in idle), diag mode OFF then the GREEN light should flash/stay on at least if both lights off continously then O2 dead. it may be similar for the RB20 ECCS since most of the software looks similar

[dojobi]

That's really weird. My O2 sensor is totally dead (ie reads 0V permanently), but I've got great economy. I've got a SAFC though, which I suppose works off the AFM.

Can anyone tell me when the ECU uses the AFM and when it uses the O2 sensor? Or is it always using both?

[darkhalf]

think it uses AFM at all times - because it requires 'LOAD' from the VQ map which is measured by AFM to calculate at least the ignition timing and perhaps air/fuel ratio maps (this uses a variation from 14.7 stioch ratio when in different parts of the rev/load range)

matt