any advice on helping me sort out emissions for mot.. Failed on high co levels.. Mechanic says seems like it's over fueling!! Just wondered if any one had and advice on how to rectify problem!
Thanks dean

 

Forgot to say it's a 1999 Impreza sti

 

Has it been de-catted Dean? Any mods etc?

 

Hi,not been de-catted, no mods totally standard except it's got a equal length manifold

 

Any luck finding out problem?

 

Try the lambda sensor .....

 

Not yet mate going to change lambda sensor .taken old one off I gave it a little shake and something inside is rattling ,so I presume it may be broken so will replace and take it back for retest ......fingers crossed

 

If it's overfuelling then the lambda reading must show this. If the lambda reading is ok it'll be the cat not doing it's job.

JohnD

 

had this problem last year. took it for a good hard drive to get cat hot then back to garage and it sailed through