ticking in head

[keith21]

there is a ticking in head of my ka24de 249sx, you really cant hear it when driving but at an idel to about 2 rpm you can hear it, any ideas would be greatly appreciated.

[Darius]

I believe the KA24DE has hydraulic lifters with rocker arms operating them on the valves. If the hydraulic lifters become worn, their full extention height is not enough to take up the slack between the cam and the valve resulting in ticking. Or if a lifter went bad and got air in it, it would no longer function properly and the result would be the same.