02 sensor live data......just change it?!

[MarkX]

I had yesterday's track day cut short due to a wot hesitation:worried:
I checked the usual, leads, plugs, tdc sensor, nothing obvious. Plugged in the RS tuner box and there was a front 02 sensor in the Orange memory, deleted and it's gone. Would this cause my hesitation?
I know the voltage should fluctuate but this seems a bit wild, low of 48mV and up to the 700s
Is this normal?

 

[MicKPM]

U/S voltage is normal but you didn't give us a large window to see it working in and without graphing the data, you will struggle to see if there's an actual fault there.

I'd say your misfire will be something else.

 

[MarkX]

U/S voltage is normal but you didn't give us a large window to see it working in and without graphing the data, you will struggle to see if there's an actual fault there.

I'd say your misfire will be something else.

Thanks Mick, I'll take a pic of the graph with both sensors when I get home. I've not seen the front 02 sensor error before.
I checked resistance at all 4 injectors and they were all 30ohms, so nothing odd.
Does that just leave the coil pack?

 

[MicKPM]

30Ohms is way too high - they should be around 14-16Ohms

 

[MarkX]

30Ohms is way too high - they should be around 14-16Ohms

I used an old analogue meter I keep in the garage, mainly for continuity, accuracy unknown but the fact all 4 are about the same would point away from them being the cause???? Could all 4 be way off?

Just took some screen shots of the oxy sensors, I'd appreciate your opinion!

 

[MicKPM]

Assuming that's at idle and the car is up to temp(?), there's definitely an issue there.

Could be sensor but could be other things also. Can you plot another graph showing H02 vs engine speed and CTS?

Idle and fast idle please (constant 2.5kRPM)

 

[MarkX]

Assuming that's at idle and the car is up to temp(?), there's definitely an issue there.

Could be sensor but could be other things also. Can you plot another graph showing H02 vs engine speed and CTS?

Idle and fast idle please (constant 2.5kRPM)

Yes, car was hot at idle. I'll do another, thanks

 

[MarkX]

Appreciate your input @MicKPM :smile:
2.5k dropping to idle and stable idle

 

[MicKPM]

Looks to be a faulty sensor trace to me but it could be poor injector(s) to. If you've really got 30 Ohms I'd guess these but I'd also test your meters accuracy to.

 

[MarkX]

Looks to be a faulty sensor trace to me but it could be poor injector(s) to. If you've really got 30 Ohms I'd guess these but I'd also test your meters accuracy to.

thanks a lot
Got home with a brand new Megger meter,
injectors 1-4
14.1
14.3
14.2
14.3

looks like I need the oxy sensor then!

 

[dann2707]

Love seeing stuff like this. Hope it sorts the issue mate.