Postby Bumpy macaroon » Sun Nov 04, 2007 9:22 am
Wifes car done same twice with hers it was one of the coil packs gone, a common problem. This will mean the engine is not firing on one of the cylinders and chucking unburnt fuel into your cat a sure fire way to end up having to fork out to replace that as well as the faulty coil pack.
Dont know how much the coil is we had ours done by AA under warrenty with renault. Have seen them on web at around the £50 mark. But it will definatley be cheaper then a new cat.. Personally I would stop driving it and get it checked just a case of plugging a diagnostic computer in (AA men carry this and coil packs, tell em its a Megane) and checking for misfire, also you may be able to notice the misfire or feel it running lumpy on tickover.
If it is the problem its a five minute repair.
Good luck

Bumpy and full of coconuts.
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