slow tick over??????

got a 1.8gti golf cab 1984 and the tick over is slow about 500rpm when warmed up any ideas at al please ,and how i could speed it up .should it tick over about 800rpm ? ta

There should be a screw on the back of the throttle body. Undo it slightly and the revs should rise. Set the revs when fully warmed then next time you start from cool check it idles at higher revs that fall until it has warmed up.

ok will have a look see if i can find screw cheers mate