Checking Lambda probes

[Daz_gibbo]

What values would I be looking for when checking pre/post lambda probes?
Check voltages with 36/33 or should I use one of the other blocks?
Not sure of the values to be looking for either...

 

[Theresias]

Depends pretty much on the actual engine you are having... maybe you could give us at least an engine code?

 

[Daz_gibbo]

2001 Ibiza 20VT so Ayp