Strange rattle when changing gear

[Pugit]

Hi i own a Peugeot 207 1.4 16v 89k miles, i have only owned it 2 months. I am getting a rattle/noise when i change gear and then begin accelerating again. I dont think its directly related to changing gear because it does it if you just accelerate from low revs. How i would describe it is a kind of metallic rattle. I can hear it with the window down, it sounds like its coming from outside the car. Its more noticeable id say when accelerating from low revs in 2nd and 3rd gear. One thing that might hold a clue is....the front bumper lower splitter on the near side was missing when i bought it, also the offside was tie wrapped on so it looks like its seen a ditch before, it was farm country where i bought it. Also a bracket on the heat shield behind the exhaust had broke off. So could this noise im getting be some kind of mount or is it more likely something is worn in the gear box?

[spider]

Its difficult to say without hearing it.

Its not the baffles starting to break up in one of the silencers perhaps ? Or maybe the exhaust manifold heat shield rattling ?

[Pugit]

Good thinking on the manifold heat shield will check it out, i know its not the lower heat shield as it has been removed to make a new bracket for it.

As for the exhaust, seems quite rusty so maybe the original

[spider]

Although not really a (great) idea, assuming its a manual gearbox with it idling (when warm as cold the idle will be too high)

Select 1st and keep the footbrake on, and gently engage the clutch a fraction, just enough to lower / try to lower the idle speed for a second. Not good to stay like this as you're burning the clutch however the idea being with a slower idle something may be a bit more likely to rattle which may help identify its location.

Heatshiled: Generally it tends to be (on most cars) the top one that fails first as it corrodes around its bolt holes. In some cases life can be extended by carefully removing a bolt and replacing it back with a suitable size (say about 15mm or so) washer on it.

[RichardW]

Sounds like good old pinking to me. Don't labour it at low revs, use decent petrol, perhaps fit a new set of plugs.