I'm not very experianced with cars, and I'm learning all I can, but now it's time to ask the gurus. There is an omnious clicking or knocking sound that used to only happen at startup, and go away after a minute or so. Now it doesn't go away. It speeds up with higher RPMs, so I'm led to believe it might be the vlaves. Anyone know what it might be, and how I could fix it? I thought driving later in the day when it was warmer would help, but it didn't.

 

ever checked valve lash before?

do a on valve lash if you dont, you'll find everything you need from there.

 

Sounds exacly like what mine did before the rebuild. When you take the rocker covers off to check the lash, if the rocker is really loose but the nut looks like its in the right place, they you most likely had a rocker stud pull out on you.

 

What'll that do to performance. Can it be fixed, or do I need to have it replaced?

 

Assuming it's 86-1/2-later, a Vette L98 will have aluminum heads, and therefore screw-in rocker studs.

Does it sound like one thing "clicking", or several? Has the engine had regular maintenance such as oil changes?

 

I'm not sure about how often the oil changes were, as I just got the car two months ago.

I'm not sure what you mean by the clicking question.

It just sounds like "click-click-click-click-click-click-click" That speeds up with the engine.

 

A couple clicks per second at idle, or several? Sounds like it is a steady sound, though, not multiple things making a similar noise.

You could try an oil change (you have verified proper oil level, correct?), with some kind of engine oil flush. Sometimes that will quiet a gummed-up lifter or lifters.

 

I checked the oil. Plenty there, but it seemed a bit dark. I'm gonna change the oil. Any additives I should look into?