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LIST OF ACTIONS REGARDING E51/E52 CATALYTIC CONVERTER ISSUES

Reverend RobP

Reverend RobP

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Having 're read this entire thread ( https://forum.elgrandoc.uk/threads/...and-the-do-not-remove-rear-cats-debate.18398/ ) again this morning here are my conclusions and the options available of which there are at least half a dozen. Rough costs are an estimate on people's postings throughout the forum. So please dont abuse me if some are slightly inaccurate!!! No agenda as I don't even own an e51 so completely impartial take on the matter.

Option 1.
Remove/decore the rear cats. Cost £100
Pros- cheap and easy. Van down time = a couple of hours.
Cons- not a 100% safe fix, and could still have future problems from front cats blocking themselves.

Option 2.
Remove/decore the front cats leaving the rears. Cost £400
Pros- eliminates chance of cat break down and blockage. Still a reasonable price.
Cons- more difficult to do, greater difficulty finding someone to carry out the work. Emissions feed back unknown. Van down time = 1 day

Option 3.
Remove/decore both front and rear cats and replace with aftermarket cats down stream. Cost £900
Pros- completely eliminates risk of old cats disintegrating. Healthy emmisions.
Cons- more expensive, very, very slim chance aftermarket cat could disintegrate in future. Van down time = 1 day.

Option 4.
Complete new stainless exhaust system with aftermarket cats. Cost £ 1200-1700
Pros- removes risk of original cat disintegration, sound lovely will last a long time.
Cons- more expensive. Very, very slim chance of cat failure. Van down time = 1 day

Option 5.
Lpg install. With full cat removal. Cost £2000+
Pros- eliminates any possibility of cat failure, cheaper fuel for future use. No emission worries at MOT as tested on lpg not petrol.
Cons- more expensive process, future lpg servicing costs, not all systems/setups are perfect causing possibility of other mechanical issues. Van down time = 3/4 days. Plus delivery/accommodation costs during process.

Option 6.
Carry on as you are with whatever process you've already done or not done.
Pros- live in a world of bliss and worry about what if's later. And enjoy life and your Elgrand.
Cons- your car could (But might not) breakdown at any moment. Expensive repair bill (£2.5k) or scrap value only.

Do with this what you will. The info is out there for anyone to read and make an informed decision on how, why, or what you want to do to extend the life of an Elgrand.
Don't think this discussion will ever go away, so long as people are still buying elgrands and not doing their homework on them.
 
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Phil said:
Excellent summary @Reverend RobP 👍
Click to expand...

Agreed

Been on option 1 for nearly 1.5 years

(Mine is regularly serviced and last summer, I also changed the PCV, had an 18" stainless steel middle box supplied and installed by @Elementian & it came with a Nismo back box, so hoping that does the trick)
 
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I went for Option 4 because I wanted a little bit more of a sound from the exhaust it's still dead quiet but I now can hear the exhaust plus it ends the problem of the catalytic converters didn't see the point of just doing the back, what I have found is the torque has increased and I seem to be getting better mpg as well but down south it will cost you between £1500 and £1700 for a complete system with 200 cell metal catalytic converters.
 
I think I will look into Option 4. Has anyone had this done recently?
 
@Reverend RobP 👍 👍 👍 nice summary - there's no perfect answer to this imperfect manufacturing issue but your precise of possible courses of action will help people make an informed choice.

OPTION 7 is to do nothing of course and some have gone that route - not me though - and for the record I went OPTION 1 three years ago - 20,000 miles on the clock then and 44,000 miles now. I keep an ever-so close watch on oil consumption and condition * in the possibly vain hope that I spot premature engine issues (due to primary cat dust) early enough :eek: .

EDIT * - I'm wondering if the fitting of an oil catch can could prove a useful 'monitoring tool' for said premature enging wear in that what is 'catched' in the catch can will be fairly consistent under normal circumstances but chance noticeably if something goes wrong- thought on this then?
 
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AlanM said:
@Reverend RobP 👍 👍 👍 nice summary - there's no perfect answer to this imperfect manufacturing issue but your precise of possible courses of action will help people make an informed choice.

OPTION 7 is to do nothing of course and some have gone that route - not me though - and for the record I went OPTION 1 three years ago - 20,000 miles on the clock then and 44,000 miles now. I keep an ever-so close watch on oil consumption and condition * in the possibly vain hope that I spot premature engine issues (due to primary cat dust) early enough :eek: .

EDIT * - I'm wondering if the fitting of an oil catch can could prove a useful 'monitoring tool' for said premature enging wear in that what is 'catched' in the catch can will be fairly consistent under normal circumstances but chance noticeably if something goes wrong- thought on this then?
Click to expand...
One thing I was thinking (and this might cause undue worry!) is sniffing your dipstick oil for a strong petrol smell.

I know there are many reasons why you may have petrol in your engine oil, but a really strong smell of gas ‘could’ be a sign of bore/ring wear?

Granted what defines a ‘strong’ smell is subjective.

the reason I mention it is when I had major work done in the front of mine by a 350z garage we were chatting about the whole cat drama and he showed me (and I sniffed) a VQ35 dipstick from a blown engine (piston ring failure due to too much boost) vs mine (slight whiff of gas). Difference was really noticeable

Just a thought really 🧐
 
Andyzz said:
I went for Option 4 because I wanted a little bit more of a sound from the exhaust it's still dead quiet but I now can hear the exhaust plus it ends the problem of the catalytic converters didn't see the point of just doing the back, what I have found is the torque has increased and I seem to be getting better mpg as well but down south it will cost you between £1500 and £1700 for a complete system with 200 cell metal catalytic converters.
Click to expand...
Thanks bud edited to reflect variations to price for full system 👍🏼
 
Pixelpoker said:
One thing I was thinking (and this might cause undue worry!) is sniffing your dipstick oil for a strong petrol smell.

I know there are many reasons why you may have petrol in your engine oil, but a really strong smell of gas ‘could’ be a sign of bore/ring wear?

Granted what defines a ‘strong’ smell is subjective.

the reason I mention it is when I had major work done in the front of mine by a 350z garage we were chatting about the whole cat drama and he showed me (and I sniffed) a VQ35 dipstick from a blown engine (piston ring failure due to too much boost) vs mine (slight whiff of gas). Difference was really noticeable

Just a thought really 🧐
Click to expand...
It's a good point, and worth people taking note!
Not to mention the fun in seeing loads of Elgrand owners walking round with oil moustaches from getting too close 😂😂
 
i went for option 1 7 years ago on my white one. Purple E51 will also be option 1 with a cross over pipe where the main silencer was and twin box quad tailpipes in place of the spare wheel holder all in 74mm diameter steel pipe, Even the pistons will come out of the back.
 
Been reading about this here and never realised this was an issue when I had our first e51. Now we are in another and was thinking of exhaust options are there any decent aftermarket bolt on exhaust headers/extractors? Other than this I am thinking of Cat back system and replacing the cats. If there is a bolt on that is decent and not stupid price. I like the car to be quiet mostly as we do long trips and kids in the back and I also already suffer from Tinnitis. :confused:. But abetter exhaust would be good as the Elgrands seem a little stifled with breathing intake and exhaust.
 
Just brought an old bored out rear cat, option 1 I guess. The van hasnt been driven in UK yet so hopefully I never have to worry
 
G'day, newbie here so my apologies if this has been brought up before re: cats. It was my understanding (from facebook groups - I know, they are definitely the best source of accurate information) that this wasn't an issue with the e51 S3, only the S1 and S2. Going by the title including the e52 I would hazard a guess that this has been reported as happening with the e51 S3's here?
 
Sorry, have to slightly disagree with option 5. Having LPG installed doesn't remove the chance of the front cats still breaking up and debris getting into the cylinders. ask me how I know!!!!!!!!!!!!!!!!!!!!!!!
 
? Option 5 says "with full cat removal "
 
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