Hi all,as some of you may know im having problems with the catalytic converter on the zed,my son was speaking to someone who used to work for the stealers,who said the cats are prone to cracking(can be welded up for £80 ish)-but the indy i went to said its because my cats going bad inside,he also said he was pinpointing the cat because of a bmw code of practise,-if the light comes on with a certain code(he never said what it was) its either the manifold,02 sensors or cat and as i have had the smoke test done and the manifod was not leaking,and he could not see the cat leaking even when fully hot, plus i have had the 2 sensors replaced by a process of elimination it has to be the cat at fault-any thoughts?,thanks.(would them running it until hot show up the same as me driving it at 60+ bearing in mind i would be sucking obviously more air in).
Catalytic problem-
- Thread starter andysat
- Start date
Andy, referring to my previous post it sounds like you are getting some better info now, if you were getting emissions lights/codes and had a cracked manifold that could fit the scenario I mentioned whereby an underlying fuel/ignition fault eventually corrupts the Cat'. What you've been told about cat faults frequently being due to repairable splits seems consistent with my experience, but cracks or splits are pretty apparent so it sounds like it's not that.
This leaves you with the prospect of needing the new Cat
but replacing the cat may not cure the underlying engine emissions fault, if you do replace it be sure that a full system analysis is carried out on the engine.
BTW from what I discovered bargain Cats are available 'under the counter' but they don't conform with the 2009 regulations requiring all non OEM cat's to have an EU type approval mark and certificate - advertising or fitting these is a serious offence and may fail the MOT so avoid. It seems you can get type approved Z4 cats for under £200 each delivered which seems cheap! http://www.catalyticconvertershop.co.uk/catalytic_converters/BMW/Z4/2006/3.0
This leaves you with the prospect of needing the new Cat
but replacing the cat may not cure the underlying engine emissions fault, if you do replace it be sure that a full system analysis is carried out on the engine.BTW from what I discovered bargain Cats are available 'under the counter' but they don't conform with the 2009 regulations requiring all non OEM cat's to have an EU type approval mark and certificate - advertising or fitting these is a serious offence and may fail the MOT so avoid. It seems you can get type approved Z4 cats for under £200 each delivered which seems cheap! http://www.catalyticconvertershop.co.uk/catalytic_converters/BMW/Z4/2006/3.0
Thinking about it tho mate,i think i am clutching at straws,surely the indy would know what they are doing?-im just a bit suss tho with all this process of elimination malarky,how do they expect customers to keep throwing money at something until they have replaced every part of the process involved?
Surely there are some definitive tests to confirm bad cats? Measurement of input and output pressures will indicate if the matrix is obstructed. Same for measuring emissions to determine if the catalyst is knackered?
While it does sound like it couldn't be much else, I can't see blindly replacing cats without some sort of definitive evidence beyond "we can't think of anything else to do". For example, any chance one of the new sensors are defective? It would really suck to blindly replace the cats, only to find it was something simple, but unexpected.
While it does sound like it couldn't be much else, I can't see blindly replacing cats without some sort of definitive evidence beyond "we can't think of anything else to do". For example, any chance one of the new sensors are defective? It would really suck to blindly replace the cats, only to find it was something simple, but unexpected.
Paying for their bloody parts usage is a pain in the arse, but for some parts, the labour to remove them and fit the original would be more than the part, and you never know if you have a combination of failing parts. The worst thing an engineer can hit is when one part takes out another and vice versa so you get into a vicious circle until you replace the entire system or subsystem in one go. Happens regularly in electronic systems.