Speaking from experience, first checking the timing cover housing. If the noise is coming from there, you either need to replace the timing set or replaces the oil pump (oil pump went out on mine, and I didn't realize it until it jumped timing.. aka "new engine time")
Replace the Harmonic balancer
Bearing noise is usually deeper and comes from farther down in the engine. Lifter noise is more of a ticking and is up in the engine heads.
NO. The engine computer is in open loop until the engine heats up to operating temperature 195 degrees are more. that means it don't hear the lifter noise and by the time the computer can, the lifter quites making noise.
hydraulic lifter? Rocker arm?
To stop engine lifter noise, first ensure that the engine oil is at the correct level and is of good quality, as low or dirty oil can cause lifter issues. If the noise persists, consider using an oil additive designed to clean and reduce lifter noise. If the problem continues, it may indicate worn lifters or other internal engine issues, necessitating a professional inspection and possible replacement of the lifters. Regular maintenance and oil changes can help prevent such problems in the future.
If there is a clicking noise get it to a mechanic you engine is blown and may be saved. Most likely you'll need a new one because a lifter is broken and it would be cheaper.
a lifter
Stuck hydraulic lifter.
A clicking noise in the engine of a 91 Ranger could indicate a problem with the valves. A valve lifter in the engine may be worn or stuck.
That is lifter noise, they probably need adjusting
Saturn vue V6 lifter noise when first started
The most common cold engine noise in a Chevrolet 4.3L is lifter clatter. Try using a lighter weight oil and see if the noise changes or goes away.