Hi...there are but the more known ones like Subang Lake (fishing) are all fished out.
Titiwangsa is having problems with its water quality.
Batu Dam allows no fishing, let alone camping.

There are popular rivers as well but they are normally overcrowded with morons who leave the place filled with rubbish after their 'nature trip'.

I suggest you join some of the local groups to discover some of the hidden places .

Good luck!

Maybe can try semenyih. I remember got some private fishing pond which near to the dam got some camping ground. But need to pay.