Last few days I've noticed a rattle coming from under the car when rpm is around 3k. Sounds like a metallic rattle, pretty much the noise you would hear when the honeycomb inside the cat breaks down, so I will assume it is that! Will check where the rattle is exactly over the weekend.

Are there any other areas I can check for rattles?

If it is the cat can it be repaired? If not I'm looking for options. I will be getting an exhaust mod done this weekend so was thinking that a test pipe and exhaust mod would be too loud.... Has anyone on here got both done? Any vids? Would a test pipe effect fuel economy?

Are there any 3rd party cats you can buy that are as good as OEM? I see a few on eBay but unsure on quality...

Finally are high flow cats any good?

Cheers in advance

 

Don't forget to check the heatshields around the cat and also in the engine bay.

 

Will do, cheers

 

I had a very similar problem recently. Turned out to be a bolt missing from the heat shield around the cat. New bolt in there and no more rattle, result!

 

Also had a couple of missing bolts from the cat heatshield causing this sort of noise.

 

Just get rid of the standard cat and get a high flow cat from berk or similar.

 

I had exactly the same mate when I had the original exhaust system on my car. it'll be that Childsy!

 

Hoping it's just a missing bolt then! That would make life easier although I am toying with the idea of a HFC...... Hmmm

 

What exhaust do you have? I had an HKS fitted at one stage that made the heatshield type sound but it was the exhaust itself at fault.

 

Only have an OEM exhaust