Within the last 18 months I have had a full new exhaust including rear box, centre exhaust, cat, manifold and gasket.

But I am getting noises from it, when I rev the car, I get a sound like stones are inside hitting the inside of the exhaust and when i first start the car up, it sounds funny.

It failed the MOT in June on emissions and needed a new breather pipe/hose.

Any ideas what is the problem?

the rattling sound is probably something loose inside one of the silencers - it could also be the cat starting to break up.

Thanks for your reply, what could of caused these problems? The car has been lowered (Before i purchased it) would this be the cause i.e catching/scrapping road bumps or pot holes.

Is this a serious issue i.e staff to drive especially long drives?

Any ideas on cost?

providing whatever is rattling inside the exhaust doesnt shift and block the gases escaping there shouldnt be any damage done.

are you able to have a look/listen under the car with the engine running - if you can determine where its rattling from might help.

I have had my cat break up before and i left it a few weeks until i could afford a new one - no issues. if the car doesnt feel down on power then i personally wouldnt be panicking

Unburnt petrol is one thing that can break the cat up internally as it makes it overheat, also driving through deep water/puddles (casues the steel to rapidly contract and crushes the honeycomb inside)

what year is your car?

Ok thanks for your help.

I'm hoping to get it checked out in next couple of weeks, as have other issues with it. As I am travelling up to Lake Districit from Kent.

Didn't want anything to happen whilst travelling up/down to there.