Originally Posted by F.I. Inc.

It is not normal and if it is faulty, I will send you out a new side free of charge. When we spoke last I needed you to troubleshoot and figure out if it was the cat or the resonator. From you last correspondence I now know it is the cat.

The cats are consisted of a 300 cell metallic core with a spun stainless steel case. The case slides over the core and than is necked down on each side to lock the core in place. Sometimes (but very rare) the core might start to move back in forth inside the case. We are talking 1/8"-1/4" TOPS! It can and never will come out of the case! Now the stainless steel expands and contracts with thermal cycles of the car. When it gets hot it expands, when it gets cold it contracts. The metallic core does not expand or contract.

Now as far as the rattling noise you hear, I do not know what that is. You are 15,000 miles away from me and I would need to hear a sound clip to pinpoint it.

I can tell you our cats are extremely high quality. They do not throw a CEL light when installed properly. They make great power and I have customers cars with 75,000+ miles on them.

Now sure can one go bad, it is a possibility. I can count on less than one hand how many have had an issue over the years. For the hundreds if not thousands that we have built and sold, I will take those percentages any day.

I will PM this directly to you as well, so we can get it rectified...

Thank you & Happy Holidays,

Tony