a lot of ppl here are concerned about the CAT thing and getting it removed from their cars, as the fuel available in pakistan is usually not 'lead free' and lead and other impurities in the fuel gets deposited in the catalytic converter and gradually choking it. as it gets choked the engine cannot breath out properly resulting in less power output and more fuel consumption. the local made cars usually don't have this thing as pakistani law does not enforce any such ruling (in most other countries cat is necessary to get the vehicle fitness certificate)
getting it removed is extremely simple and i have no idea why toyota walay are charing so much (someone said Rs. 3000) for this.
first of all, you'd need to park your car on a dock or get it lifted so that you can work on the underside of your car. for this you can go to any roadside mechanic or silencer wala.
locate the CAT, in most of the cars, including vitz, its just after the exhaust manifold, (actually in the same assembly) its a bulged thing (4-5 inch thick) (local mechanics will call it dholki)
unscrew the joint between the manifold and exhaust pipe (its held together by two large bolts) and you should be able to see the CAT through the open joint. use a torch or spotlight of some sort the peep in.
you should also be able to feel it with a rod or screwdriver.
if you still don't have enough room to work, you can unscrew the mounting of exhaust pipe at the middle of the car. (in vitz, its held by two 10mm bolts)
the CAT is actually made of some ceramic like substance, so now you have to break it into pieces and it would come out from the pipe (be patient, this would take some time and effort). you can use a large phillips screwdriver or metal rod like barbque wali seekh, or saria with sharp edge, or cheiney)
cover the neck of the dangling exhaust pipe with some cloth so that dust and particles of CAT may not go into it.
there is some cotton like insulation material round the cat, since cat operates at extremely high temperatures. make sure you get that out as well
be careful while breaking the cat so that you donot damage the sensor located just above the cat, although its not very close to it, but still care should be taken.
after getting everything removed from the dholki, put everything back together and there you go
you can see the CAT in this pic, its taken from directly under the car, a difficult position to take pic though
this is how the exhaust pipe would look like after unscrewing it.
