I have thought of that too espetially with the plug appearing to refill.?

I have the codes now,
p0130 o2 sensor circuit b1 s1 low voltage.

p0130 o2 sensor circuit b1 s1 range/performance.

I think this is the first time the low voltage code has appeared. I just noticed my aprentice has written the same p codes for both so one isnt correct p code.

Its back in tommorrow i think so i may tweek open the back of the ecu to see if its full of oil. The only place i can think of it coming from is the pressure sensor is there anywhere else it could be from??

regards Brad