xxxxSMITHYxxxx
Registered User
hi all i have just had my fault codes read and it said after cat 02 sensor fault is there more that one 02 sensor on this car then?
hi all i have just had my fault codes read and it said after cat 02 sensor fault is there more that one 02 sensor on this car then?
I take it the pre cat is the one you can see from under the car, closest to the exhaust? Mines just failed MOT pretty badly on CO emissions and lambda, not sure whether to get new sensors or buy a second hand cat.
Been getting P0171 'system too lean (bank1)' and P0420 'cat system efficiency below threshold (bank1)' for a while, if I clear them they come back within weeks.
Allan
Thanks tuffty, so you'd recommend a new catalytic converter? I'm on a budget so gonna try source a second hand jobby. Does this one look ok, comes with post cat sensor as well. AUDI S3 A3 8L Exhaust Twin Cat Catalytic Convertor K04 1.8T BAM 225bhp 1997-2003 | eBay
Allan
Hey Tuffty, I could have possibly found something under the inlet manifold with the PCV breather pipes. I have noticed the one part of plastic that looks like a Y shape has a pipe to the right of it touching and just sitting inside but not properly sealed. Thought that maybe you can push and they would click together but no luck. Doesn't look like there is meant to be a clip either.
Here's a picture, part is labelled 058-133-753-B and to the right is the pipe that just sits inside loosely.
Thanks again,
and Smithy ill PM you in a bit regarding the vcds program.
Thought id update the post, I fitted the new pipe under the inlet manifold and what a pain those old Audi clips are!!! Car felt better straight away smoother through the revs and idles much better. Also fitted a new panel filter as my old one looked knackered and changed plugs, cleaned MAF and the throttle body.
Ordered a new cat few days ago, second-hand one from a breakers for £120. Went to get it fitted today and was told the part was too short by a few inches and the diameter was smaller, brilliant! Anyway they hooked up the emissions machine as they were curious to see how bad it was and surprisingly it had got better, but was still not passing.
They told me to put the Cataclean in that I had bought earlier in Halfrauds and to go for a blast up the motorway for half hour or so. Did this and went back and it passed straight away.
CO went down from 1.487 to 0.197
HC went down from 57 to 19
Lambda went up from 0.960 to 1.000
Idle test CO was originally 1.493 and now is 000.5
Anyway Im happy, gonna try get a refund on cat. The garage seem to think it is the precat lambda sensor playing up but hopefully it just needed cleaning, time will tell....
Allan