I have recently purchased a mk1 octavia VRS, I was told that it had a de-cat when I bought it and that they had to take the lamda sensor off to fit it and that was why the engine management light was on. It's clearly running very rich and not doing many mpg's so what are my best options? Where should the wiring for the lamda come out? Is it running in limp home mode at the mo because if it is it still feels quick enough. Any help would be much appreciated and despite these minor problems I am loving VRS ownership!

There must be at least one lamda probe in the exhaust (usually two)

With a decat you get a engine light unless you have the second lamda probe mapped out by a tuning company. Little can be done apart from getting the sensor mapped out, or putting a cat back into the system. Without a cat the car will most likely fail an mot test or a roadside spot check. my old vRS with a sports cat would barely pass the mot and needed to be good and hot before the test.

It might be cheaper for you in the long run to get a sports cat fitted instead of the decat.

With the decat it sounds like your car is drinking fuel like nobodys business, you would have to pay a remapper to get rid of the engine management light, and come MOT time you have to find a friendly tester... or mess around swapping a cat in just for the MOT.

You could probably sell the decat pipe to cover most of the cost of a sports cat

Thanks for the replys, so roughly how much would I pay for a sports cat? and would that have a hole in for the second lamda or would I still need to get that mapped out?

Send a PM to sivrs he's one of the VRS owners on here I think he bought a downpipe and decat and then got a sports cat welded in in place of the decat, it was a lot cheaper than buying a downpipe and sports cat complete, which is what you usually have to do.

Sports cats should have the holes for both lambda sensors.

Send a PM to sivrs he's one of the VRS owners on here I think he bought a downpipe and decat and then got a sports cat welded in in place of the decat, it was a lot cheaper than buying a downpipe and sports cat complete, which is what you usually have to do.

Sports cats should have the holes for both lambda sensors.

i certainly did, got an un silecenced de-cat downpipe off ebay just under £100 then paid £150 for a sports cat to be fitted. miltek want £410 for there downpipe and sports cat

HTH

si

Edited 21 May, 201016 yr by sivrs