Hello ST buddies, I've not been posting much lately because work has been hectic but I thought I would come on to see if someone can ID a problem for me.

Basically, my car makes a mettallic sounding noise, imagine if a wasp was made of metal, thats what it sounds like. It happens when my revs go past 3200 RPM and gets louder towards 3300RPM then goes completely at 3400RPM. As you can see, it only occurs over a small range but if I'm in 5th on a M-way doing 70ish miles per hour it can be constant.

Happens in all gears, quite confused. Checked oil, was a bit low so I toppped it up, no use.

Some theories (rule them out if you can)

Fuel type? Used supermarket fuel a lot lately, doesnt seem like it would cause that at specific revs tho

Resonation? Could a bolt or screw have come loose and it sings like hell when the RPM matches the natural rythm of the offending item

Something bent in the engine? This is pure guesswork..

Other than that i'm stumped. In second gear if I accelrate to 6.5k RPM slowly its like rrruuuuuuuuuuuuummmmmmm(wasp noise)mmmmm(wasp noise goes)rrruuuuaaaaaahhhhhhhhhhhhhhH!!!!!! change. Hope that helped.

BTW... Ran my car to 0 miles left then filled it to brim with BP fuel. Was hammering Dubstep all the way to work so I didn't hear it but i'll take my car out in a sec and update if the wasp noise remains.

Catalytic Convertor stuffed?

Right, tested the fuel, no joy.. Lifted the bonnet and held the revvs at that mark and something is buzzing, sounds like its coming from the engine bay but I have no mates and cant check it out, i'll do it when I see my mates tommorow.

Robjh, I know what the cat does but I have no clue what the symptoms would be like... I assumed the buzz was from the engine bay but I could be mistaken.. Do you know ruffly how far down the exhaust the cat sits?

its not the manifold heat shield fallen off and only vibrates on the exhaust when at those revs? could be anything lose...

Hmm, heat shield sounds like a possibility. I'll have a raid around tommorow, i'm fairly certain is isn't critical now so i've calmed down a bit. I'll update here if I do sort it. Thanks team ST.

I have the same problem, If i am doing 70mph on the motorway then plant the throttle it has the same noise like yours! Like a coin in a tin can rattling but only does it at 3000-3500rpm. Mine is a 08 with 15k on the clock.

I've still not had chance to check out where its coming from exactly. It doesnt sound critical and it isnt getting worse, i have done about 500 miles since i made this topic.

whoop whoop what do i win?

To spend a day with jedward!

Hmm the bolts are rusted in. I've had a 'fiddle' with it, i'll see if that helps. Cheers guys.

Re-bumping this one.. can I remove my heat shield??

I have removed the standard air box... will it be safe to unbolt the two screws and take off the metal heat shield?

you should be fine taking it off, cause if you change it for a sports manifold the heat shield wont fit back on!