I have recently noticed a vibrating sound when my cars revs are low. According to a friend its the exhaust manifold heat plate/shield vibrating against the beginning of the exhaust. He told me to bend it away from the exhaust by pushing a long metal bar against it! Thing is, which way do I bend it? Towards the exhaust or away from it?...

Hello, I would wait till the engine is cold and then wobble the exhaust plate by hand to see if its at all loose. The vibrating could be due to something else and you need to have a feel to be sure.

I had a similar sounding problem but it turned out the exhaust gasket had gone on No.4 and the blowing was causing the metallic sound - possibility if the shield isn't loose!