Valve chatter or spark knock?

[Crazy Horse GT]

Originally posted by HorsPowr
I have real bad (what I think is ) spark knock in upper RPMS and ESPECIALLY when air conditioning is on. Any advice? Ive heard its due to carbon build-up dealing with the EGR - will replacing the EGR help?

My engine is very strong and solid but high mileage. I probably need new plugs though and a tune up anyway.

yeah im getting the same thing from my 95 gt vert, but it was bought by me from a retired guy, all he did was polish the car , i have started modding it, same problem, not all the time though, guess, i'll try the old cheater trick, pour a little bit of tranny fluid in the engine. i'll let you know what happen's. btw i did a tune up it did decrease it alot.