Thanks to all who posted ref my blocked cat issue (buried in the 'temperature sender thread!). I followed Tony2005's suggestion and took out the front Oxy sensor to see if the performance improved - if it did it was a marginal improvement - maybe the hole just isn't enough to allow the engine to breath well? Anyway I was after comments on the Oxygen sensor itself - I have no experience as to what these things should look like - mine was black & sooty - does that help with the diagnosis - I'm thinking too rich in the mixture - not enough air getting through - therefore blocked cat???
Can the oxygen sensor be cleaned? And lastly it looks like a 4 wire sensor in front of the cat and a 2 wire sensor behind - why is that?
Thanks, Malcolm
