Silence at the back.

[Spiny Norman]

I'm no mechanic, but does the following sound like a failing silencer to you?

 

Couple of days ago, the EML came on for one journey, then went out again the next time i started it. Seemed to run OK while it was on so I didn't worry too much.

I also noticed going through the downhill section of a tunnel with the window open where you're on over-run for a good 30 seconds there was a noise I can only describe as a loud sort of zzzzzzzz-ing rattle, quite metallic sounding, appearing to come from under the car which went away after a few seconds.

Loose baffle/blockage maybe?

[richardmorris]

Sounds like a blocked exhaust/cat yes.

[Pillock]

Try giving the cat a tap. Not a punch-a-hole-in-it smack with a hammer but a gentle tap with your knuckles will tell you if it's rattly and broken inside.

[Spiny Norman]

OK, tried that. Couldn't reach it with my hand but I gave the cat a light tap with the rubber handle of a hammer and while it sounded very tinny and metallic and quite hollow in places I'm not sure I'd describe the sound as rattly or broken.
 

Close up it's definitely coming from either the cat or the rear silencer, and sounds like the grating metallic noise you get when you try and grab reverse a bit quick.

[the judge]

loosen front pipe or manifold bolts and try then

[Jim Bell]

Def sounds like youve dropped a washer in the intake with the carb off.