I have a 1997 Mitsubishi Montero LS 3.5l
I'm experiencing aloud noise at idle. CLICKING NOISE. WHEN driving at high rpm don't hear it as much. Soon as I come to a traffic light the sound is unbearable. Change my oil regularly. In the mornings its quiet until I put it in gear. Sounds like im shuffling cards. Please help

 

Sounds to me like it could be the hydraulic tensioner for the timing belt. I have a 2001 Montero Limited that has had that fail twice in the last few years. Very loud at idle/stop lights, making it sound like a diesel.

If it sounds like this then it may be that tensioner:

 

I had a sound like this recently and couldn't pinpoint it. Not quite as loud, but worse on cold start-up. Happened to be searching around in the engine bay and noticed the housing around the cooling fan had cracked with age at the top and a piece was hanging down in the way of the fan blades, causing them to strike it. Rap, Rap Rap Rap. Very loud. Broke the piece away and no noise since. Would be nice if it were that simple for you!

 

Does not sound like the tensioner

 

I have a 2001 Mitsubishi Montero Sport Limited and I also had a loud clicking/rough probing noise coming from the middle of the engine. Come to find out my water pump and timing belts were slipping slightly out of time. In all the clicking noise is probably your timing belt and water pump having issues. Best to change them at around 100,000 miles each time.