leaking cat causing running problems

[leew88]

My ph1 failed its emmisions yesterday on the lambda reading,the other 2 were ok

The car has stood for months which was why thought it felt a bit lumpy but since having another look the the cat to centre section gasket is leaking (got one to go on in the morning) its about 2" downstream of a lambda

Is this likely to cause my symptoms?

best way i can describe how it feels is like a old carb'd car like a cortina lol

 

[Timmsy]

depends how much your emissions are out TBH,

mine failed the other day and was at 5.3% which is 5% over what it should be, replaced the cat, stealth cat back and new gasket, still failed again. was better but not enough. had to replace Lambda, hey presto... done