Catalytic Converters - anyone has one for sale? :(

ga41

Veteran
 Paphos
Hi guys, went to have my car MOT'd yesterday morning and they wouldn't pass my car because of too high emissions. They said CO2 spiked abnormally and my lambda reading was all over the place... The guy there said my catalytic converters "have gone bad" or that maybe there's a leak somewhere sucking in air.

I'm having the engine smoke tested on Monday to check for that but in the case that the fault is indeed with the converters does anyone here have a set lying around that i could buy off you? It'd obviously have to be in working order.

Buying new from here is more than 1500 euro and i think it's about the same from the UK... If you guys have any other ideas on what might be at fault please post. My car has got RPI exahusts and the RPI scoop but no other engine/exhaust modifications.
 
It could be one of the sensors themselves as they do go bad, but not heard of a cat 'failing' for a long time - even my 20 year old e34 M5 passed on its original cat.

If it is the cat then you may be able to fit a racing cat or aftermarket non-BMW one instead - but don't know where you'd source one in Cyprus.
 
I had my Lambda sensors replaced about a year ago and have no fault codes on the car whatsoever... Really strange! And the trouble now is that i can't have the car MOT'd anywhere else now (in case their equipment itself was the issue). It has to be the same centre. :headbang:

The link you posted shows of converters for engines only up to 250hp though.
 
As mmm-five says, your cat shouldn't fail, and certainly not at the age of your car. Seems odd, but perhaps the o2 sensor is starting to fail but not yet thrown a code up.

Hope you get it sorted!
 
ga41 said:
The link you posted shows of converters for engines only up to 250hp though.
It was just an example, as I know you can get them for almost any power engine.

Is the tester claiming both (separate) cats have failed at the same time? Which would be VERY unusual.

Unfortunately I think the two cats are attached to each other, so you can't replace just the faulty side without cutting & welding.

If you do need them replacing then you might as well go for aftermarket ones as they'll cost about the same.
 
Besides leaded petrol, what other elements can damage a cat?
 
mmm-five said:
ga41 said:
The link you posted shows of converters for engines only up to 250hp though.
It was just an example, as I know you can get them for almost any power engine.

Is the tester claiming both (separate) cats have failed at the same time? Which would be VERY unusual.

Unfortunately I think the two cats are attached to each other, so you can't replace just the faulty side without cutting & welding.

If you do need them replacing then you might as well go for aftermarket ones as they'll cost about the same.

He didn't mention anything specific about one or the other, simply said they've broken/gone bad (it was in Greek anyway :P ). I didn't even think about having them check the other side exhausts, they only did the right ones. Didn't even come to my mind that they're actually 2 different systems from header down..

pvr said:
Besides leaded petrol, what other elements can damage a cat?

pvr, i've read that extreme heat can damage them too, say from unburned petrol running through them... I did have the car running very rich at one point a year and a half ago due to the bad O2 sensors.... I'm sure it's the rubbish quality of our fucking fuel out here. :x


To be honest i'm completely lost about this. Don't know what to do...
 
ga41 im not sure these people are right.... ive been running my car with 507+ HP in 30 deg C heat sometimes ALL day track sessions and still my stock cats are fine and performing fine, our cats are a 400 cel high flow units and i simply cant believe your cats are bad, its a possibility but i extremely doubt it....... my cats have probably got the hottest on this forum with the power the car makes and use it see's....... i would personally pull them off and inspect them yourself, you'll clearly see if they are shot.... these units are proper high quality, im guessing failures happen but it just doesn't seem right......

ive ordered the DKF system from front to back so my entire system, apart from those lovely CSL manifolds will be up for sale once it lands...............
 
Beedub said:
ga41 im not sure these people are right.... ive been running my car with 507+ HP in 30 deg C heat sometimes ALL day track sessions and still my stock cats are fine and performing fine, our cats are a 400 cel high flow units and i simply cant believe your cats are bad, its a possibility but i extremely doubt it....... my cats have probably got the hottest on this forum with the power the car makes and use it see's....... i would personally pull them off and inspect them yourself, you'll clearly see if they are shot.... these units are proper high quality, im guessing failures happen but it just doesn't seem right......

ive ordered the DKF system from front to back so my entire system, apart from those lovely CSL manifolds will be up for sale once it lands...............


That failure does not make sense I agree. MMM5 does it make sense to only test one of the outlets? Sounds like dodgy / badly calibrated equipment to me.

GA41 I presume you kn ow these guys well? if not, I would get it tested somewhere else just to make sure that there is actually a problem.
 
I'm not sure whether the centre silencer mixes the gasses from both cats or not. If it does then you'll likely get the same result from either side - which is an average of the output of both cats.

I'm not sure whether the Z4M uses metallic or ceramic cats, but ceramic ones usually 'tinkle' when driven slowly over rough roads as the broken bits rattle in the casing.
 
ChawenHalo said:
That failure does not make sense I agree. MMM5 does it make sense to only test one of the outlets? Sounds like dodgy / badly calibrated equipment to me.

GA41 I presume you kn ow these guys well? if not, I would get it tested somewhere else just to make sure that there is actually a problem.

I dont know the testing center that well but i can't take it anywhere else now, it's logged in as unsuitable and has to be tested at the same place again.

mmm-five said:
I'm not sure whether the centre silencer mixes the gasses from both cats or not. If it does then you'll likely get the same result from either side - which is an average of the output of both cats.

I'm not sure whether the Z4M uses metallic or ceramic cats, but ceramic ones usually 'tinkle' when driven slowly over rough roads as the broken bits rattle in the casing.

They don't rattle i think but it's hard to check with those exhausts that i have. I'll have my garage inspect them visually when i take the car in on Monday for the smoke test.
 
Just had a talk with my mechanic, smoke tested the engine and found no leaks but when they visually inspected the converters he said they are definitely shot and need replacing... I may go the custom route and have an exhaust shop fab me some universal converters on there but it still isn't going to be cheap, i was quoted around 700 euro for that +/- 100 euro.... :cry: I'm waiting for a specific quote from them now.

Well, at least there's some good news, apparently i solved that hesitation problem i've been having on low rev throttle blips. Bought new coils and sparks for 270 euro and the coils have cured the hesitation according to my mechanic, the sparks will go on tomorrow because i couldn't source them in time.
 
This can only be due to you running it rich for a while, surely. I would think your best hope is to find some cats at a breaker?

http://www.ebay.co.uk/itm/BMW-E85-E86-Z4-Z4M-3-0si-BREAKING-PARTS-SALVAGE-/270855725076?pt=Automobiles_UK&hash=item3f10426014

That's the only one that came up but it's 10mins from me - so if they have them & you made them a GBP offer I'd be happy to help if they're funny about sending to you.
 
Andy said:
This can only be due to you running it rich for a while, surely. I would think your best hope is to find some cats at a breaker?

http://www.ebay.co.uk/itm/BMW-E85-E86-Z4-Z4M-3-0si-BREAKING-PARTS-SALVAGE-/270855725076?pt=Automobiles_UK&hash=item3f10426014

That's the only one that came up but it's 10mins from me - so if they have them & you made them a GBP offer I'd be happy to help if they're funny about sending to you.

Thank you for the offer Andy, very much appreciated. I'll definitely keep it in mind. :thumbsup:

It didn't even occur to me to check at breakers. I'll have a mosey now.
 
Got a quote for a set from a 57 plate Z4M for 534 pounds, including shipping to here. Sounds good?
 
Did you tell him your car was off the road?

Offer them £500 all in & see what they say, but with Christmas coming if they say No I'd probably still snap them up & get them on the way.
 
Just got another quote for 425 with shipping! Will have to call them tomorrow morning to confirm though because the only detail in the email is that they're used catalytic converters, the end.

425 doesnt sound half bad.
 
thats bad luck mate but then our cars do need a bit of TLC, they're not golfs with all that performance... and fast driving :poke:
 
Turns out the 425 one was without VAT. I fucking hate it when any business does that. When clients come to me i tell them the full price, no "Oh right, that's without VAT." when they decide to a deal.

Anyway the original 535 quote was reduced to 475 so i went ahead with that one. He said they'll send it off on Monday, hoping i'll have it by end of next week.
 
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