84 z28 305

The motor runs perfect at idle with no knocking. But once you rev it up past 3 grand it will knock real bad and then stall out. It is a loud knock on the drivers side. I can then restart the car and it will run great and quiet as can be until i rev it again. The oil pressure is fine with 30lbs at idle. I also checked the oil and found no metal shavings.

Anyone have any suggestions as to what could be causing this?

 

get a hose, long screw driver or even a stethscope and pin point the location of the noise

 

I like my 2' of heater hose for this purpose. Works like a charm.

 

good news. Had my neighbor check it out. It turns out that a valve is sticking and the knock was coming from the piston hitting the valve. He recommended trying an additive first. So i picked up some of that cd2 valve detergent and it actually worked. I let it run for 20 minutes and kept on revving to 5 grand and have had no problems. Guess i got lucky with this one.

thanx for the replies

 

"Good news" and "piston hitting valve" never belong in the same paragraph... IF your piston was hitting the valve you'd have lots of trouble ...nothing some junk in a bottle you buy at a store could fix.

 

yeah piston to valve contact = major damage