Hey guys! I just had a mechanic investigate why my car was throwing a CEL and the P0420 code along with a catalytic converter conversion code. He told me the cat has broken down. I don't know if this is true, but since the cat inside has broken down and is restricting flow, the heat shield above the turbo shakes aggressively. I know OEM cats are crazy expensive and I'm trying to sell my car to upgrade into an R59 Roadster S. What should I do that is cost-effective but will survive for a while? Recommendations for in the Boston area would be highly appreciated!

 

I'd just like to clarify that my '08 Cooper S has around 124,500 on the odometer and has had a lot replaced on it.

 

The shaking of the heat shield because of the broken down cat is a bit puzzling. Are you suggesting that the restriction of the flow is causing the cat to vibrate that causes the heat shield to vibrate? If that’s the case then that’s going to cause a lot of problems to the connected parts as well especially turbo etc.

I believe the only cheap way you can get an OEM cat is through a salvage yard or one of the good people in here, maybe eBay. Tons of cat less cheap option but that will throw a code and you won’t be able to sell the car.

I would first buy the roadster, take the cat out and install it on the cooper to sell. Put a cat less on the roadster and tune the car! Now you have an extra fun car!!!

 

I appreciate the reply! I'm selling my R56 to afford the roadster. Having 4 cars at my house is not feasible at the moment unfortunately. I've found some leads on used ones though so hopefully I can snag one with around 50k miles on it

 

I do have some good news! I sold my car yesterday with the issue. A mechanic purchased it and he will fix it up. It's in good hands now. Soon, I will be acquiring a 2012 R59 Roadster S with the JCW Aero Kit and the GP2 belly pans and diffusers. The car was well-loved, one owner, has had no major issues, and is a blast to drive. It has a manual soft top which is one less thing to go wrong along with no Navigation. The previous owner installed a JB+ tune to it and it felt more powerful than my tired '08 MCS. Once I acquire the roadster, I'll be doing a full post about it. Oh and before I forget to mention, it comes with two sets of wheels, 17" Enkei's with winter tires and 18" Breyton Race GTS-R's with shot summer tires. Summer, if it isn't as depressing as right now, will be a blast.

 

I thought I would add that I need a cat for a 2009 MCS if you hear of anything, mine has blown and I can't re-register. Congrats on your new ride!

 

Some few years ago, I needed to replace a converter on another car (a Boxster). The original converter on I forget which bank now (error code P0430 but I'm too lazy to look up which bank this refers to) had a loose brick that sometimes shifted out of position and triggered the error. All the time it knocked at cold start and buzzed like crazy when hot.

I sourced a pair of used exhaust manifolds -- the converter being part of the exhaust manifold -- and had a tech swap out the original pair for the used one. Problem solved.

Price ($450/each) of the used converters less than half the cost of factory new ones.

If you pick up a used converter shake it to ensure nothing loose or broken inside and nothing comes out. Handle the converter with care. Don't throw it about.

Or if you want in some states that have emission testing there is a database of converter manufacturers which offer replacement converters supposedly at a discount to the factory converters.

Check the CA CARB site for a link to a converter supplier database and find a company that offers a replacement convertor for your particular car.

Or look here:

https://www.hottexhaust.com/pages/fi...SACEgKtFvD_BwE