Ouch - that is as bad as the phase 2 item at €274 I just paid. I can get these much cheaper from my contacts in Switzerland (just under €100 a few years back). Does this forum support group buys? Wouldn't be quick enough for you though John.
It is quite common on phase 2 my99/00 cars for a neglected car to have both a failing MAF (which under-reads, causing less fuel to be added), and a failing O2 sensor (under-reading again, causing more fuel to be added) - these 2 tend to cancel each other out in closed-loop fuelling mode, only becoming apparent when one is changed and the ECU reset.
Having said that - I have no experience with my04 mechanical failure issues. They were still new when I was working on them :wink: Probably best to find someone with the same MY or phase of car willing to do a quick swap?
Failing that, if you can get to D4 I can plug in a laptop with EcuTek and quickly tell whether O2 sensor is gone.
Richard