I have this error, and ive found a dodgy wire going into the sensor on the oil filter housing, how ever when i google this error there is no mention of this error being linked to the wire ive found, but refers to the sensor under the car fixed near the oil drain plug.. any thoughts?

The sensor on the housing is oil pressure.

Do any (UK) Mk1 Fabias have oil level sensor?

That's a good question, I've worked on that many from the vw range they all blur into one, I want to say yes but could easily be an audi or something.

My Polo's got one - bottom of the sump - but I've not seen anything about them on here as far as I remember (not far). 

perhaps the 

Oil Level/Temperature is either or in vcds world, so where is the oil temperature sensor?

Does your car have an oil temperature displayed anywhere?

 

You've been swapping ECUs and recoding various things, haven't you? Think something's not quite as it was.

Does your car have an oil temperature displayed anywhere?

no lol

presumed its a engine management thing, perhaps not.

see edit to my last.

Does your car have an oil temperature displayed anywhere?

 

You've been swapping ECUs and recoding various things, haven't you? Think something's not quite as it was.

 

Yes true, i haven't altered "instruments" thats where the fault is registering

Maybe just forget about it and enjoy the car a little while first.

http://www.amazon.com/If-aint-broke-fix-until/dp/B00PCL9QZW