knocking on idle

[zim zimma]

hi all i have a 96 318ti and iv noticed and knocking/clunking noise when sat at idle can fell car shake idle is a bit lumpy aswell. And secondly my temp guage is on half way never had it that high before allways sits at the first mark on just in the blue is this something i should check out thanks .

[marti5]

Could be your water pump or thermostat,as the temp gauge should sit at 12 o'clock, dead in the middle, all the BM's Ive ever driven are always in the middle.

[zim zimma]

its hardly ever been in the middle since iv owned it just stayes around the blue heaters are good is it a easy job doing the pump and stat and could this cause the car to idle rough thanks.