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citroen saxo - engine warning light on - alan73

hi my wife has a citroen saxo 1.1 2000 on a w reg the engine warning light came on yesterday so she had it pluged in and got code p0420 the car runs and pulls fine just when engine is warm tick over is up and down sounds like its chokeing been told is a air leak then told its the 02 sensor now been told its the cat dont know where to start with it carnt be the cat because it passed mot last week unless they go wrong in a week just dont want to waist 300 pound on a cat at garage if it will not fix the problem any idears how i can see wot is the fault with out spending a load of cash spent 30 pounds haveing it plugged in and still havent got a clue wots wrong with it thanks for any idears darren

citroen saxo - engine warning light on - MrEckerslikefromRamsbottom

Have a look at this American site for ideas..


In the comments at the bottom of the page, #22, headed '2001 Toyota Corolla', 'Sam' says that he got the P0420 code, filled up with Shell V-Power and the light went out within a week! Anyway, there's some useful info in there. Some of these American posters say that they got the fault code after changing the 'header'. What the Hecky Thump is a 'header'? Have I got a header? Or am I one?

I like this one...


Edited by MrEckerslikefromRamsbottom on 15/07/2012 at 14:27

citroen saxo - engine warning light on - alan73

had a look and think il change the 02 sensor had a look at cat looks fine sensor is very rusty and a header is the top half of the engine you can change vales for biger ones gives engine more bhp and thanks for the help

citroen saxo - engine warning light on - t j auto electrics coventry
Try using some decent fuel and maybe adding a fuel system cleaner to boost cat efficiency, drive the car hard for about 20 miles this should burn any contaminant from the cat, supermarket fuel usually has no additives in it to keep cats clean, it is cheaper to run on bp ultimate as you will get more mpg and fewer garage bills.... Try it, you may like it .....tony
citroen saxo - engine warning light on - skidpan

Headers in the states are the exhaust manifold.

Just because it passed an MOT a week ago does not mean the cat or O2 sensor can fail a week later.

Its an old car and things can go wrong.

By all means try running it on expensive petrol that is little better than the standard stuff but I would be very surprised it it performed a miraculous cure.


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