Strange ticking sound

OK so i have a 1998 Tacoma 4x4 with the 3.4L. The only mods is a K&N intake. For the last few months my truck has been making this loud clicking type noise. It only happens when im sitting at an intersection with my foot on the brake and it is in drive. If i put it in neutral it stops, but then starts again quietly. It almost sounds like an air conditioning fan is hitting a shroud or something, but i know it is not that because it happens even with the air turned off. It sounds as if it is coming from the engine compartment, but only on the passenger side. Any ideas let me know cause it is very annoying.
Thanks, Matt

 

I got a click coming from the top driver side of my engine. Mine is the 3.4 liter. Does yours have a rythem to it or is it off and ion? Mine sometimes has a rythem andi sometimes its just intermittent