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E51 The E51 Catalytic Converter Problem

But most cars don't have such a setup and perhaps for the obvious reason lol.
Probably more than people would think. It seems Europeans tend to fit them on the performance models even though a stupid design, I suppose manufacturers don't think so as they class them as a lifetime part but their lifetime is shorter than ours. Not sure about base models, BMW M3, Audi RS3, Mini Cooper, seem to have them and most likely others.
 
Even my old Citroen C5 V6 had a secondary cat. Never got blocked but I had to replace it as it rusted out.:confused:
 
I'd never heard about secondary cat problems before I got the Elgrand, but definitely something to check if buying a large engined or performance car.
 
I've been following our feed above with great interest as its going to help me when I buy an Elgrand towards the end of the year; I am planning to buy a vehicle that has already been imported; however, I do have one question (as stupid as it may sound), what are the early symptoms that show the rear cats starting to clog-up?
 
I read somewhere on here that a smell of Petrol in the cabin could be a symptom. Could be mistaken tho!

Edit; this is the symptoms for the fronts, not rears
 
as It’s the rears it’s easier to just get them either decored or just replace them. @Winchester supplies and fits nice empty ones for around£150
 
I've been following our feed above with great interest as its going to help me when I buy an Elgrand towards the end of the year; I am planning to buy a vehicle that has already been imported; however, I do have one question (as stupid as it may sound), what are the early symptoms that show the rear cats starting to clog-up?
From what I've read on here you might not get any symptoms before damage is done. Don't take the risk...just get rear cats removed or decored as your first job.
 
100% de core or replace with straight through pipes .
 
It does happen with other cars, the Honda Civic has a range that suffers from this but as there is only one exhaust being a transverse 4 cylinder the engine stops after a few minutes running and wont restart until pressure in the exhaust front pipe drops, some of these double cats are put into a single housing which the Civics was. The fact that the Civic stops and wont run saves the engine whereas our V6 engines have 2 independent banks of 3 cylinder each side each having their own double cat system and that is why we keep driving until its too late as even not running fully on one bank of cylinders the VQ engines still produce quite a lot of torque and 9 times out of 10 the average owner wont notice until its too late and emptied their bank account.
MY STRONG ADVISE IS GET IT DECORED OR SELL IT AND BUY SOMETHING THAT IS NOT AS MUCH FUN.
 
Well said that man .😎👍👍👍👍
 
Many thanks for the response for other forum members, this info is going to help "Big Time"..
 
I have owned my 2002 E51 since 2014 and hadn't been aware of this issue until I stumbled on this web page several days ago. Due to go on holiday in it over the next few weeks so really pleased to have read the warnings about the rear cats clogging. I have ordered some de-cat pipes as a result. Removed the secondary cats today and pleased to say they are clear, however not taking chances. thankyou for the advice.

edit - sorry not 2004 - donut - it was a fresh import in 2014!!!
 
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No sorry - of course it wasn't 2004 - typo - I bought it in 2014!
 
It’s the rear cats that are recommended to be removed, because any debris from failing front cats can block the rear cats, causing terminal engine failure.

I offer a de-catting service on an exchange basis, based in Hampshire UK. If you are too far away, I now offer a mail order option, de-catting and refurbishing and VHT protecting your own rear cats.

Here they are, before and after...
View attachment 8911
Hi Adrian are you still doing refurbished cats for E51 2002 ,if so how do I go about getting them , and postal service. Regards Bob Manor 7325
 
Hi Adrian are you still doing refurbished cats for E51 2002 ,if so how do I go about getting them , and postal service. Regards Bob Manor 7325

Yes Bob, I’ve always got sets ready to send out, send me a pm with your details and I’ll get a set organised, regards Adrian
 
Yes Bob, I’ve always got sets ready to send out, send me a pm with your details and I’ll get a set organised, regards Adrian
Hi Adrian you’ve saved my sanity, I can’t tell you the hassle I’ve had with these cats , unfortunately I don’t know how to do a pm , regards Bob
 
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