Response from Fabspeed!
We are seeing a small percentage of cars having the issue you are having with the slow o2 response. To be honest it hit us out of nowhere as none of our long term test mule cars had any issues. We just redesigned the downpipe for the 335i and your 235i. So far have only had the new design on test mule 335i’s because that’s all we could get our hands on. It has 100% corrected the issue you have on the 335’s and It should do the same on the M235i. Today in 20 mins I have a new test M235i coming in to have the new design installed. As long as it check out we are going to phase out and replace any dp’s that have caused issue. I will see what I can do about getting the part installed for you at one of our distributors near you as soon as it’s ready. Please hang tight in the meantime, the cat you have won’t cause any damage to your car other than the annoying CEL. I apologize again, we will be reaching out to all our customers shortly with a polished version of this same response, also a forum post. We wanted to let everyone know that we are a stand up company and stand behind our superior quality product.
I HAVE GOT TO GIVE IT TO THEM FOR BEING %100 TOP NOTCH! PERFECT RESPONSE AND SOLUTION! OVERALL THE DP IS AMAZING I GUESS A VERY SMALL % OF US RAN INTO THE UNFORESEEN BUG BUT THANKYOU FABSPEED FOR THAT PROFESSIONAL RESPONSE I AM VERY HAPPY WITH YOUR COMPANY AND PRODUCT REGARDLESS OF THIS ISSUE A FEW OF US ARE DEALING WITH!
