Nissan Repair: 89 nissan hardbody truck, nissan hardbody truck, haynes manual

Question
i have a 89 nissan truck with the z24 engine. just got. it has 8 plugs but i was told it was still a 4 cylinder? i never heard of this. i also has a loud noise coming out from under valve cover, like maybe bad cylinder. but no loss of power and no suction from tail pipe. please help. still runs but noisy.

Answer
Twila,

Two plugs per cylinder on a four cylinder gives you more power and reduces pollution.  But, you noise is most probably the valves needing adjustment.  The hot lash setting is under the hood on a sticker.  Remove the valve cover and get a Haynes manual to see photographs of the procedure to adjust valves.  The plugs should be changed if they have not been done in a couple of years.