It pretty much taps all the time. Cold or hot. Idle or revving. Can't hear it from in the cab. Unable to tell without a stethescope where it is coming from. Seems more prominent on the drivers side front. I didn't put a lot of time into diagnosing because I just wanted it fixed and dropped it off. Doesn't seem to get any worse since I've owned it. Approx. 3,500 miles driven. Really sounds like a valve, but then again it doesn't. I'll probably try and check it this weekend and I'll keep you posted. If I take the valve cover off I still won't be able to see the tensioner, so we'll just have to see when I get in there.