Hi, I need to pick someones mind, my 2001 octavia 1.8t vrs has just failled it's mot on the emissions . The mechanic suggested a new front lamba sensor so I bit the bullet and bought one and had it fitted, the car failed again, same problem, so a new catalytic converter was suggested, again bought and fitted, same result although emissions were greatly reduced but still over the limit.

The engine was remapped about 3 or 4 yrs ago, I bought it 2 yrs ago, it has passed the previous mot's with the engine remapped but not this time. I have run some injecter cleaner through it, fitted new coil packs and spark plugs and the engine is flushed out on every service and now and again I give it a good thrash to clear out the cat of any crap that may not have been expelled by my normal gentle driving style and I am now seriously short of cash.

If anyone has had a similar situation or knows of a cure for this problem I would very much appreciate your help, oh and by the way I have never had any dash warning lights come on.

My best regards to all briskodians,

Ian

I'd start by using VCDS to determine what fault codes, if any, are logged, rather than randomly throwing parts at it.

Can you post up the readings as well. I tested an Audi TT with 225 BAM engine in it a while back and the CO was way over at 7%, the fault with that turned out to be a disconnected fuel temperature sensor, that didn't have a warning light on either.

I had the same problem at my last mot. Ended up taking it to skoda and having them flash my ecu cos of a **** r tech map in it.

Remap was making it overfuel way to much. Get someone who knows what they are doin to check your fueling mate