My injectors makes a clicking noise but its nowhere near as loud as a rod knock, and cant be heard when the hood is closed, esp from inside the car.
If the knock does not get louder with throttle then it is likely top end related (which is better than bottom end).
Do you have an oil pressure guage? You might not be getting a lot of oil to the top end at low rpm. You should get a guage, or remove the valve cover and make sure oil is getting pumped on the cams when the engine is being turned over.
90 Nissan 240SX - SR20DET swap
Mods: Full rebuild with ARP head and rod bolts, 3" exhaust, K&N filter, E-fans, and a Walbro 255lph fuel pump.
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