peckingnoise in engine

[rifsm1]

My 2000 Firebird has around 70,000 miles on it and I've had a few problems with it in the las few months. I've had the plugs and wires changed,the enginebelt (serpintine) and now I have a pecking noise in my engine. I know nothing about cars, its not bad until I rev the car up and as it goes back to Idle you hear peck peck peck. Any ideas to what this is?? I am almost ready to get rid of it

[RAF7789]

-you say the noise does NOT speed up when the engine speeds up?
-what grade fuel do you use?

-have you tried to locate the general region of the noise?
-pop the hood and start your engine
-get a long dowel metallic or wooden
-touch one end of the dowel to a NON MOVING part
-and hold the other end to your ear
Good Luck!

[msfyter]

Piston slap or a bad lifter.

[rifsm1]

I just started using plus grade fuel

I just got back from town in it and it also did the noise when I was speeding up but it sounds worse when its winding down

[Joe 1320]

If it the noise increases in frequency and volume with RPM and load, it's likely the rod or crank bearings, possibly a bad wrist pin. If it only gets faster with engine speed and doesn't have anything to do with load, then it's probably something in the valvetrain.