[N1rve]

Hi Folks!

Recently I've been hearing a metallic scratching noise upon cold start up. It doesn't always occur so it's very difficult to record the noise. Sometimes it will happen once every 3 days, and sometimes it will happen once every 3 months.

It doesn't seem to relate to temperature either. To describe the noise, I would have to say it's a sound of crumpling paper really quickly or someone shaking a bag of rocks with metal shavings. The noise only lasts for a split second and goes away quickly.

The only exhaust mod I have is a Perrin 3 Inch exhaust. Everything else is stock.

I'm going to check the following this weekend:

1) Exhaust Shields
2) Mounting Points/Connection Points of exhaust
3) Check Starter (to see if it's grinding on the fly wheel but I highly doubt it).

Anything else to check? Could it actually be the baffles inside my Perrin muffler has gone/loose? Ideas on how to check that?

Car is a 2013 Scion FR-S 10 Series. It has push button start. Automatic Transmission. 56k Miles.