Technical Cat cracking

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Technical Cat cracking

harrison1980

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Joined
Feb 19, 2005
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Location
West Yorkshire
Hey all,

A few months ago my cat cracked on my 2001 Bravo HLX and so was replaced, just recently the replacement one developed a crack and was replaced, and now no more than 200 miles later that one is developing a crack...can anyone tell me, what would cause the cat to crack???

Thanks in advance

Harrison1980(Rich)
 
cat cracking means it is overheating. is it also changing colour? an orange tinge would be a good clue.

unburnt fuel enters the exhasut either when weak ignition is unable to burn all the fuel or if there is a leaking exhaust valve. you said you have an HLX but you dont say if it is 1.6 or 1.8. i will assume it is 1.6 because this problem is common on the 1.6 and rare on the 1.8. the reason it is common on the 1.6 is fuel injector faults. an injector spray that is too thick can not burn, allowing unburnt fuel to enter the exhaust where it ignites when it hits the hot cat.
 
Hiya Jug,

Yes it is the 1.6, wouldn't say it was changing colour as yet but this cat is in the early stages of cracking and only slightly noticeable when accelerating, maybe i'll notice a change in colour as it gets worse, thanks for your reply, i'll mention your points to the garage when they replace the cat again under warranty as i'm sure this time they'll want to find out why rather than just replace it again

Rich
 
After much careful deliberation, no overheating / changing of colour evident, any opinions / help muchly appreciated
 
get an emissions test done and check the HC's and lambda, high HC's point to a misfire or fuelling problem somewhere - there is absolutely no point replacing a cat without making sure the engine is running properly as the replacement will expire fairly quickly.
 
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