Clogged Cat - BMW M140i - Professional De-Clogging
Discussion
Dear all,
due to pandemic (and limited use anyway), my car has driven only to the station and back (3 miles) for a year now. It started to misfire and BMW said the reason was likely to be the clogged cat (heavy smell of petrol and, I think, sulphur; I wouldn't know because my nose isn't very good). They say the cat doesn't get warm in the short travel to/from the station and the cat slowly starts to clog, until misfire occurs.
BMW generously offered to put a new cat in the car (38,000 miles) at the price of £1,311, but I want to explore other solutions first as I know cats can be cleaned (BMW told me they don't do it..). I want to try to avoid having to have an expensive new cat installed after only 38000 miles.
I am a total disaster in matters of mechanics, so it will have to be a professional putting his hands on it. Therefore, dismantling and doing it myself (provided there are people who do it) does not come into question.
Car is now parked at my parking space below my flat. It's so clogged now it does not want to start. But even if it started I would not trust me to drive around in it with some cleaner in the fuel tank. I want to have the cat thoroughly cleaned and be done with it.
My questions:
1) How complicated is this? Is it something a mobile mechanic could do at my place (if there's need for electricity I have my windows above the car and an extension cable can be used), or will the car have to be brought to the specialist?
2) Can you give me names of specialist who do this? I live in Essex, UK, near Lakeside shopping centre. perhaps are there national specialists with a franchise you would trust?
3) Is this a "specialist" job or is this something which, in the end, every car mechanic with his head on his shoulders could do?
4) Is it true what BMW implied, that third parties cleaning the cat could "ruin" it? Honestly, I am tempted to call BS on it for obvious reasons.
Many thanks for your help!
Omobono
due to pandemic (and limited use anyway), my car has driven only to the station and back (3 miles) for a year now. It started to misfire and BMW said the reason was likely to be the clogged cat (heavy smell of petrol and, I think, sulphur; I wouldn't know because my nose isn't very good). They say the cat doesn't get warm in the short travel to/from the station and the cat slowly starts to clog, until misfire occurs.
BMW generously offered to put a new cat in the car (38,000 miles) at the price of £1,311, but I want to explore other solutions first as I know cats can be cleaned (BMW told me they don't do it..). I want to try to avoid having to have an expensive new cat installed after only 38000 miles.
I am a total disaster in matters of mechanics, so it will have to be a professional putting his hands on it. Therefore, dismantling and doing it myself (provided there are people who do it) does not come into question.
Car is now parked at my parking space below my flat. It's so clogged now it does not want to start. But even if it started I would not trust me to drive around in it with some cleaner in the fuel tank. I want to have the cat thoroughly cleaned and be done with it.
My questions:
1) How complicated is this? Is it something a mobile mechanic could do at my place (if there's need for electricity I have my windows above the car and an extension cable can be used), or will the car have to be brought to the specialist?
2) Can you give me names of specialist who do this? I live in Essex, UK, near Lakeside shopping centre. perhaps are there national specialists with a franchise you would trust?
3) Is this a "specialist" job or is this something which, in the end, every car mechanic with his head on his shoulders could do?
4) Is it true what BMW implied, that third parties cleaning the cat could "ruin" it? Honestly, I am tempted to call BS on it for obvious reasons.
Many thanks for your help!
Omobono
Seeing as it doesn't want to start it's likely the internal matrix has started to break up and those pieces are doing the clogging. Those kind of clogs don't normally come from exhaust gas. It'd need removing to diagnose that properly though. The cat on these is an inch from the turbo so should warm up very quickly. To answer your questions:
1) Removing the cat is really a workshop job, but it could be done on a driveway.
2) Cat de-clogging isn't really a thing like say intake walnut blasting is.
3) I don't think they'd know where to begin, probably with something long and pointy, but they could certainly replace it at a lower cost than BMW (I would be investigating this if it was me).
4) Yes.
1) Removing the cat is really a workshop job, but it could be done on a driveway.
2) Cat de-clogging isn't really a thing like say intake walnut blasting is.
3) I don't think they'd know where to begin, probably with something long and pointy, but they could certainly replace it at a lower cost than BMW (I would be investigating this if it was me).
4) Yes.
Edited by Pastie Bloater on Saturday 24th April 13:10
Omobono said:
Many thanks Pastie Bloater,
when you say "yes" to Number 4, do you mean "yes" that it is BS or "yes" that BMW is right?
Cheers
O
No worries, I'd say yes BMW is 'right' in that if it's let's say full of carbon trying to un-clog it could ruin or damage it, as there isn't really a known effective way to go about doing so. I'm not aware of any chemical means (beyond the supposed in-tank ones) and mechanical means will just damage it. when you say "yes" to Number 4, do you mean "yes" that it is BS or "yes" that BMW is right?
Cheers
O
Belle427 said:
Probably time to get a nice sports cat fitted!
Good shout! I'd go for 200 cell for ease of passing the MOT.Thanks all again!
To answer some of the questions: BMW already checks possible issues "before" the cat (spark plugs, injectors) and found everything hunky-dory.
What I will now do is wait some days until I start the car again and see whether it starts, at that point the liquid I have put into the tank should allow some improvement. If not, it's going to be a new cat all right.
I did not know of the existence of "sports cat". Can you tell me more?
1) I assume it's MOT legal?
2) Advantages and disadvantages?
3) Why was it not part of the standard equipment?
Many thanks to all again!
Omobono
To answer some of the questions: BMW already checks possible issues "before" the cat (spark plugs, injectors) and found everything hunky-dory.
What I will now do is wait some days until I start the car again and see whether it starts, at that point the liquid I have put into the tank should allow some improvement. If not, it's going to be a new cat all right.
I did not know of the existence of "sports cat". Can you tell me more?
1) I assume it's MOT legal?
2) Advantages and disadvantages?
3) Why was it not part of the standard equipment?
Many thanks to all again!
Omobono
Omobono said:
Thanks all again!
To answer some of the questions: BMW already checks possible issues "before" the cat (spark plugs, injectors) and found everything hunky-dory.
What I will now do is wait some days until I start the car again and see whether it starts, at that point the liquid I have put into the tank should allow some improvement. If not, it's going to be a new cat all right.
I did not know of the existence of "sports cat". Can you tell me more?
1) I assume it's MOT legal?
2) Advantages and disadvantages?
3) Why was it not part of the standard equipment?
Many thanks to all again!
Omobono
It's not legal if it passs the emissions test they are less restrictive then a OEM cat Hence "sport's"To answer some of the questions: BMW already checks possible issues "before" the cat (spark plugs, injectors) and found everything hunky-dory.
What I will now do is wait some days until I start the car again and see whether it starts, at that point the liquid I have put into the tank should allow some improvement. If not, it's going to be a new cat all right.
I did not know of the existence of "sports cat". Can you tell me more?
1) I assume it's MOT legal?
2) Advantages and disadvantages?
3) Why was it not part of the standard equipment?
Many thanks to all again!
Omobono
The downside is they aren't as efficient at reducing the pollution
Strange! It does what it is supposed to do but it is still illegal?
Can you imagine other issues, e g insurance making difficulties?
If I can rely on it passes MOT I am not really concerned about how "standard" it is, unless there are other issues...
I'll see if the forum has discussions about this re reliability etc.
Thanks a lot!
O
Can you imagine other issues, e g insurance making difficulties?
If I can rely on it passes MOT I am not really concerned about how "standard" it is, unless there are other issues...
I'll see if the forum has discussions about this re reliability etc.
Thanks a lot!
O
You don't want to fit a "sports cat" what you need is a proper diagnosis on what is actually causing the issue & if the cat is stuffed you need the proper one.
I suspect as has been mentioned above there is currently an un-diagnosed issue causing a cat problem, so if you sort the cat the underlying problem will then goose the replacement cat.
Cats don't really get clogged up.
I suspect as has been mentioned above there is currently an un-diagnosed issue causing a cat problem, so if you sort the cat the underlying problem will then goose the replacement cat.
Cats don't really get clogged up.
Omobono said:
Thanks all again!
To answer some of the questions: BMW already checks possible issues "before" the cat (spark plugs, injectors) and found everything hunky-dory.
What I will now do is wait some days until I start the car again and see whether it starts, at that point the liquid I have put into the tank should allow some improvement. If not, it's going to be a new cat all right.
I did not know of the existence of "sports cat". Can you tell me more?
1) I assume it's MOT legal?
2) Advantages and disadvantages?
3) Why was it not part of the standard equipment?
Many thanks to all again!
Omobono
Forgive me but do you realise the liquid only works when the engine is running, and through significant quantities of fuel? There won't be any improvements just by adding it to the tank or soon after starting.To answer some of the questions: BMW already checks possible issues "before" the cat (spark plugs, injectors) and found everything hunky-dory.
What I will now do is wait some days until I start the car again and see whether it starts, at that point the liquid I have put into the tank should allow some improvement. If not, it's going to be a new cat all right.
I did not know of the existence of "sports cat". Can you tell me more?
1) I assume it's MOT legal?
2) Advantages and disadvantages?
3) Why was it not part of the standard equipment?
Many thanks to all again!
Omobono
To be fair if you're not well up on these kinds of mods I'd focus on just getting it fixed. Your engine can make plenty more power with the stock cat before it becomes necessary to move to a sports cat, so it's probably not worth worrying about. They can pass, fail or be borderline depending on the 'cell count' and volume, and it's a declarable mod for insurance.
Hi, yes I do get the engine will have to run for the fuel and the de-clogging liquid to work.
I think that a probable cause of the issue is the long series of short travels, where the cat never gets warm and causes the clogging. At least, this is what BMW thought the most probable cause of the issue. As the potential causes "before" the cat have been already examined and it was found that there is no problem, I think there is a good probability that BMW had it (potentially) right.
What I want to do is to avoid spending £1311 if I can avoid it. Just as an example, BMW charges £186/hour (VAT included) for the work, the local BMW authorised workshop charges £54 (VAT included) for the same work.
When BMW comes and changes the cat, I think they will be able to see whether an issue remains after the installation of the new cat, then we will take it from there.
However, if next weekend the car starts and the engine runs halfway normally, I will try with driving around with the cleaning liquid and see whther it was just as simple as that.
Thanks again
O
I think that a probable cause of the issue is the long series of short travels, where the cat never gets warm and causes the clogging. At least, this is what BMW thought the most probable cause of the issue. As the potential causes "before" the cat have been already examined and it was found that there is no problem, I think there is a good probability that BMW had it (potentially) right.
What I want to do is to avoid spending £1311 if I can avoid it. Just as an example, BMW charges £186/hour (VAT included) for the work, the local BMW authorised workshop charges £54 (VAT included) for the same work.
When BMW comes and changes the cat, I think they will be able to see whether an issue remains after the installation of the new cat, then we will take it from there.
However, if next weekend the car starts and the engine runs halfway normally, I will try with driving around with the cleaning liquid and see whther it was just as simple as that.
Thanks again
O
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