Fumes after new Cat

[simonben]

I have a 02 Corolla and recently had a new Cat Converter fitted. Now, fumes are entering the cab, the garage can't find why, they replaced filters and checked seals. Any ideas ? Anyone ?

[TonyHSD]

Hi, 

In later models 2010 and above there is specific way how the metal gasket is placed between cat and exhaust manifold., and between mid and rear silencers pipes. If they turn the gasket the other way around these will leak and no matter how tight they do the nuts. Best to check all connections for leaks while engine is running and redo, replace the gaskets. Using high quality aftermarket or original Toyota parts. If a garage done the replacement then they should find the fault and fix it before giving the car back. We had same issues after new exhaust was fitted and the garage couldn’t get it right 3 times, then we went to Toyota service next door and they fixed it in no time and explained that to me. 
Good luck 

[oldcodger]

On our models , 2006 which should be very similar to yours and the metal gasket @TonyHSD mentions comes in two different sizes, a smaller one for the front pipe and a larger one for the mid to rear.

Both are like compressed wire wool but have very distinct surfaces. one side flat the other domed to fit the concave of the pipe, so should be rather obvious when fitting and probably clearly seen if fitted the wrong way around.

If leaking you/they might want to try a thin layer of sealer on the concave surface of the pipe  only a little as you do not want the whole gasket to become solid, its supposed to flex a little.

Even though new ,  It could also be a leak from one of the cats welds / seams, though if you can smell it inside the car it must be quiet a leak, possibly ask for an inspection at another garage and see if they they find.