Okay so I was getting ready to leave work one night (I work at a Toyota dealership) and when I started my truck I heard a very slight tick. I pulled it into the shop to get a second opinion. Then tonight when I went to move my truck I heard the tick bit it was a little louder. I got out, popped the hood and have it a little gas at the throttle body and the tick was louder at maybe about 1500 to 1750 RPMs ( complete guess. I have no tack.) btw my truck is a 97 4.2 v6 with 197k on it. Could the noise be lifters and if so how hard would it be to replace them?

 

Does it go away when the engine is up to temp? If so it's more than likely a manifold leak. If not its still could be a manifold leaking that would be what I would look at first. If its a lifter go to the auto parts store and get some crc i think thats the brand engine restore it comes in a big soda can looking container And try that first. I had an old toyota that had a bad lifter and that shut it up for 3000 miles or so then it would start ticking again so an oil change and another can and it would shut up.