Hello folks my timing chain has had a rattling sound for a while, not too noisy but I don't like noise so I visited my mechanic and we had to use a new tensioner but both the old tensioner and new one needed an assistance of a self tapping screw to hold the tension. If you just fot the tensioner in position and lock it, it locks just fine but after you've replaced the timing cover etc and get ready to start the car, the first few seconds of starting it will rattle as if there's no oil or there's delayed pump action then it will idles nice and quiet thereafter, this lasts for about 5 seconds. So the mechanic removed the new tensioner which is probably cheap Chinese stuff and put back the old one which is likely original but the same thing happens unless you place a self tapping screw on the tensioner and keep it locked up, nice and tight. Do you guys know why it's doing this, could it be poor quality tensioners? Please advice, thanx.