Not the Cat curse again - surely?
 

The list gets longer! :(

2 cats on my old A8, 2 new 'sports' cats on my S8, a new cat on my daughter's 206 just after we picked it up and, after standing close to briang9's S8 at the Scotland mini-meet, his cat went too!

Then my engine management light came on again, so I swung by A4 Audi on the way home last week and the VagCom said both cats were out of tolerance. But the light went off the following day and has stayed off for a couple of hundred miles or so.

The new cats are only around 7 months old and under guarantee, but is it likely to be them or maybe just a bit of gubbins in the petrol (BP Ultimate, always)?

Any thoughts guys?

BTW - I'll stand well away from your '8 at June's meet for a small fee! :)

Which lambdas where showing the fault. If it's the one after the CATS then it will probably be because you have sports cats.

Not sure. I'll call Andy and see. Why would the sports cats make the warning light come on and then go off again?

You have a FL S8 Jim, with Lambdas before and after the cats. The ones after the cats monitor the efficiency of the cats. With the sports cats there are generally only 100 or 200 CPI whereas in the standard cat there is 400 CPI. The more CPI the better the cats clean up the exhaust gasses. The less CPIs the better the car performance. The post cat Lambdas are probably registering the exhaust gasses out of programmed range occasionally and throwing a fault. There is a modification that can be made to the lambda housing that eradicates this problem.

Here is a thread on the subject.

This thread discusses the technique to alter AFR; but it is the same for post cat lambdas to stop faults.

Thanks again oh font of all knowledge! :)

Might pop back to the guys who fitted the cats and ask them to do this

na na na na CAT MAAAAANNNNNN!!! :snigger:

Out of interest how much are a pair of cats for a 4.2 V8? Might aswell know what I'm getting myself into!

Got mine done last week, around the £500 for two sports cats, I did contact an Indie in the Area and they wanted around £1200 to fit only one of the Genuine Audi ones

I 've spoken to Semtech and they're more than happy to take the car in and honour the guarantee. The sports cats are 200 cpi, apparently, compared to 400 dpi standard. Stevie said they only fit 100 dpi to track cars.

But, anyway, the light went off after around 24 hours and hasn't come back on in a few hundred miles. So I'm hoping for a glitch from a bit of gubbins.

BTW - can I change my user name to 'Catman' and keep my 'senior member' status?

I can change it to "Catman" but the location keeps coming up as "back garden" and the status's available are either "Sleeping" or "Spraying" :p