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Stock Problems/IssuesDiscussions related to warranty related issues and repairs, or other problems with the OEM parts and software for MINI Cooper (R50), Cabrio (R52), and Cooper S (R53) MINIs.
I have an exhaust leak, and I'm considering replacing this can (see arrow in pic) with a straight pipe. I have a couple of questions that I need help answering:
1. What is the function of this can?
2. What can I expect if replaced with a straight pipe welded in after the second O2 bung?
3. Is 2.25" the correct size of pipe?
You can try to re-weld it, straight pipe it (but will get a CEL sometimes), but check with your state on the laws or go with a performance option like milltek that has the Cat and the factory bungs.
Isn't the cat specifically the portion between the two bungs in the diagram? I see three portions in the diagram, the flex pipe, the cat, and that last can. What is that last can? Is that a second cat of some sort? I want to replace just that last part with straight pipe, but not if it's going to smell noxious.
Isn't the cat specifically the portion between the two bungs in the diagram? I see three portions in the diagram, the flex pipe, the cat, and that last can. What is that last can? Is that a second cat of some sort? I want to replace just that last part with straight pipe, but not if it's going to smell noxious.
The diagram isn't correct if we're talking R53...
If the part you're referencing is indeed the cat, and if replaced with a straight pipe, I think you'll have to live with a constantly illuminated CEL on the dash, as well as the possibility of failing emissions tests depending on where you live.
Unless I'm mistaken, the exhaust components are as depicted below. Please correct me if I'm wrong.
Last edited by AoxoMoxoA; Apr 14, 2017 at 10:57 AM.
Reason: Corrected Photo
You can try to re-weld it, straight pipe it (but will get a CEL sometimes), but check with your state on the laws or go with a performance option like milltek that has the Cat and the factory bungs.
Originally Posted by AoxoMoxoA
The diagram isn't correct if we're talking R53...
If the part you're referencing is indeed the cat, and if replaced with a straight pipe, I think you'll have to live with a constantly illuminated CEL on the dash, as well as the possibility of failing emissions tests depending on where you live.
Unless I'm mistaken, the exhaust components are as depicted below. Please correct me if I'm wrong.
The stock headers have two cats and usually crack and leak at the small cat joint in ECS's picture. AoxoMoxoA'S diagram is correct, but leaves out the small cat between the pre-cat o2 sensor and the main cat. Here's a pic from the other MINI forum. http://www.*********************/for...75-post41.html.
The stock headers have two cats and usually crack and leak at the small cat joint in ECS's picture. AoxoMoxoA'S diagram is correct, but leaves out the small cat between the pre-cat o2 sensor and the main cat.
Appreciate the help. Looks like I'm going back to the search button to choose a header that a cat can be welded to. I'd like to buy a header with cat included but I'm not comfortable with the $1000 price tag yet.
Part of me still wonders if the first cat might do enough to get by without the second cat. That being the case if I put a straight pipe in place of the second cat. I'm assuming most of the feedback is from people that had no cat at all.
get it welded... shop will remove header, fix w welding, and reinstall....much cheaper than replacment... a straight pipe really isn't the best option... loud and will fail emission
Put a magnet up to it, it it sticks, it's good stainless, use stainless rod, if it doesn't then it doesn't matter what you weld it with, stainless steel rod or an old coat hanger.
