What could it be?
 

Bout 2 weeks ago my car started to make this knock/clatering noise. Its not coming from the bottom of the engine.

I baught valve cover gaskets tightened up the rockers at tdc put the valve covers back on it still makin the noise. I am confused a bit on wat it might be. I cant hear it all the time but its very annoying. Under a load it seems to get lil worse.

Could it be bad egr, knock sesor, ect..?

Car is a 92 z28 lb9 tpi.


Ne ideas or help would be greatly appreciated.

Re: What could it be?
 

By what you done you're assuming it's coming from the valve train.
Be specific, what procedure did you use to adjust the rockers? If done inproperly you could have made the problem worse.
There are DTC codes for the EGR (32) and KS (43.)
Does check engine light work?

Re: What could it be?
 

I do believe its a valvetrain knock i thaught maybe since the car had gotten sluggish as well that maybe egr went and its a spark knock but i believe its a lifter is there ne thing i can use the free it up or make it stop?

Re: What could it be?
 

You're just guessing here, try to diagnose a little better first. Is the noise coming from under or near the valve covers and is it regular like a metronome - if so then most probably valvetrain.

Pull the valve covers and turn it over, make sure all the rockers are moving and by equal amounts.

As rga asked above, exactly how did you 'adjust the rockers'? From your description, you imply you set them all without rotating the crank. If so you'd get a helluva noise and loss of performance!

Re: What could it be?
 

Sounds to me like the rockers are loose still/again, but could also be a broke valve spring, though if it were that it would barely run. Lifters sticking make more of a ticking sound, not clattering/knocking.