I have a rattle coming from the engine and I am wondering if anyone has any idea what it could be. I only hear it when I am accelerating. It gets to a certain rpm depending on how fast I am accelerating and this rattle starts. It is only when I am accelerating. I can rev it up and nothing happens, it is only when I am in gear. I was thinking it might be a heat sheild and was wondering if anyone knows where I should start. I know heat sheild are on there for a reason but I am wondering how wrong it would be to take one off and see what happens.

i've just finished dealing with a similar problem.

the collar on one of my lifter assemblies broke, flipped onto the lifter beside it and was banging on the valve cover.

not being able to hear it when you are standing over the engine makes diagnosing a little hard since you can't hear where it's coming from.

often a rattle can be pinging, go to ogres cave (link at the top) and read up on ping and knock and see if that kind of describes your problem