Is this a dead (or dying) O2 sensor?

[djstatic]

My car is always pretty lean (on-going saga). Today it was mega rich and it was sustained for a long time.

Here it takes a dive and stays down for about 5mins


Then it comes to life for a short while only to die for the rest of the journey


Should I replace it, or look elsewhere?

BTW I would have posted this in Mechanical (had the permissions allowed me) sorry for stinking up the Type 2 forum

[djstatic]

When I say dead, it's really flat-lined (the other pictures perhaps don't show the severity)


Short Term Trim hits the roof too.

[Matt]

Shouldnt be reading towards 0 if your lambda is around 0.8

If you hold at 14.7:1 closed loop it should swing above,below 0.5 volts with about 0.2 lean and 0.8 peak point. That one doesnt look so great

[djstatic]

Based on the other post I figured I'd add 1% to TIM and see how it affect my afr's.

Drove to work with not much changing. After work I added another 1% and not much changed.
Stopped at the servo (E85 life) and 20min after filling up, crazy rich. My car is never rich.

How soon after changing TIM does the change take affect?

[Matt]

Trims start adjusting straight away. I used an R32 (and also cefiro A31) ECU in my R34 for testing yesterday and found the short term trims start adjusting within seconds. Long term gradually catches up

[djstatic]

I was meaning, change TIM by 1%, hit apply. Should it be instant?

[Matt]

Injection time will be affected immediately

[djstatic]

It must take a lot if altering to get the AFR's to move then.

I've got it running "ok". I still have that persistent lean delay after shifting.

Might be time to visit a tuner. I have a new turbo, manifold, etc.etc. I'm just trying to buy some more time for other parts