Vehical is a isuzu trooper '90 with 90,000 mi has a loud ticking noise when running and driving it has something to do with the engine. Oh and it's the loudest when u first start it. It's not the pistons or rode it has been going on for a long time 6 mths or so but it is internal, it hasn't taken any power away and is not the fan or timing chain.
The ticking noice you need to narrow down where it is. It could be the fan blades hitting the outside of the fan cover, or if it is internal it could be a lifter that is pinging. Try to narrow down the location of the noice for better help.