l have bought an old Vauxhall Corsa, The plastic bumpers are very faded does anyone know what l can use to restore the original colour?

you can buy a product from halfords to brighten up your
bumpers

Are the bumpers black? If they are what you need to do is soak all the visible parts of the bumper with loads of Back to Black. You can get this from your local car shares shop. Forget the instructions on the can, spray the back to black onto the bumper almost as if its a can of paint spray. Once you have coated the bumper do not polish it off leave it for 10 mins and then rub of the excess.
Ja.

There are several products available at places like Halfords..look for something like Auto Glym back-to-black.

Boot polish, cheap and cheerful. All the sprays tend to make it look great for five minutes and then they fade straight to grey again. Corsas always suffered with this.

Orrrr what you could do is just colour code the bumpers and arches and spray them :)
thats what l done on mine it looks loads better !
but if not .. yes look for back to black, messy stuff but works brilliantly if u use a good brand !

The best way to restore the colour permanently is to use a heat gun on the plastic. Be careful not to go too close to the bumper as it will melt. this will bring the colour back and it will stay, not like the back to black which is good until it rains and is washed off!

If there black plastic use armor-all protectant[mint stuff].if there colour coded use T-CUT.