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Discussion Starter #1
Hello, my Mk1 Phase 2 Laguna seems to have what looks like hair / fur coming out of the exhaust pipe - I am right in thinking this means the cat has collapsed internally?

Or did I just reverse really quickly over a proper cat and don't remember? :devil:
 

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Administrator
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I was going to say it was from the cat, but it could be from the backbox. The only really way you'll know is to get underneath and give cat and backbox a good thumb to see which one knocks when hit.
 

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Discussion Starter #4
If its the baffling from the back box then I can live with that. So far the car doesn't seem down on power (as a collapsed cat would suggest) or any louder - its the first time I've noticed this fur stuff today though so I think its only just started.

MOT is due in 2 weeks - will it pass if its the back box? A knackered cat will screw the emissions test I guess.
 

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Universal
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Usually when the CAT is fecked it will glow red hot, plus the car will give off some nasty smells from the exhaust. So if it's none of these, then the others may be right about the backbox, but you should be able to tell if it's gone louder.

Are you positive nobody has shoved something in the exhaust? :d
 

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The wife's picasso only recently passed its MOT with collapsed baffles in the back box. It was flagged up as an advisory. Her exhaust was noticably louder though.
 

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Discussion Starter #8
Perhaps I'm going deaf in my advancing years then!

Fox - there's no funny smells that I've noticed, fuel consumption is the same, no excessive heat as far as I can tell. I did get some odd looks as I was pulling this stuff out of the exhaust in Asda's car park, but its pretty well lodged in there - don't think it's someone's pet anyway!

Dave - think i'll book it in early and hopefully it'll get through with an advisory
 

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Discussion Starter #10
Whatever was coming out of it disappeared over the weekend, so I booked the car in for its MOT on Thursday. I got home tonight and there is a big trail of it coming out of the exhaust pipe. Oh the joys!

Rear silencers don't look too expensive from GSF, I'm hoping it passes though.
 

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Whatever was coming out of it disappeared over the weekend, so I booked the car in for its MOT on Thursday. I got home tonight and there is a big trail of it coming out of the exhaust pipe. Oh the joys!

Rear silencers don't look too expensive from GSF, I'm hoping it passes though.
Sounds as if it was fooling you into a false sense of security then ! :rofl:

I suppose as long as the exhaust isnt excessively noisy it should pass. May also be worth cutting off any of the hair stuff that's poking out that morning, just to be sure. ;)
 

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Looks like the inner insulation of the rear silencer box has collapsed inside.
If any of it gets trapped in the internal baffles the car may fail its exhaust emmisions test especially when at idle. Obviously in this situation the mpg will be badly affected. Once the metal retaining cage for the insulation fails then the baffles will probaly fail soon after. In other words it's rusting from the inside out.

CAT's usually only get hot when unburnt gases reach their high temperature innards. This normally only occurs when there is a serious engine fueling or misfire problem.:)
 

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Discussion Starter #13
Well, it passed on the exhaust :d Looks like its the baffles collapsing in the backbox then?

It did fail on the rear pads and front track rod ends, which I was expecting. Not bad for 20k miles in a year
 

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Tourerman
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I had the same happen to me with a Granada I had, the fibre packing blocked the exhaust and stopped the engine running, when I cleaned out the blockage with a long strip of metal it seemed to run better with no extra noise!

Like having a straight through performance box.
 

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Baffles are metal strips and or pipes (or similar gubbins) fixed in the silencer which interrupt the gas flow in order to absorb the sound energy. The hairy stuff is packing that is also in the silencer to further absorb sound energy.
 
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