Ok, just checked the sensor that came off the car, it indeed looks different to the one we put on. The one that was on the car originally has a shiny head (looks like metal) with holes in it, the replacement one has a ceramic head with no holes but instead has about 4-6 lines from the top of the tip to the base (these lines are a few mm deep and wide with a gap to let the fumes through.

I'm contacting the guy from eBay to check this is the right one since its not working and we believe it is wired up ok.

 

Seriously though if theres nothing wrong with the car (you'll know) i wouldnt bother replacing.

 

This is what I was afraid of....

 

Just a quick update on MPG, previous to new sensor I was struggling to get 200 miles to a tank, today i filled up with V-Max

 

Not sure if you was referring to me or not but I have had a problem with hesitations and poor fuel economy, thats why I changed the sensor to hopefully cure the problem - I certainly wouldn't have changed it otherwise, thats just daft.

 

Looks a lot like my Zeitronix wideband.