Rare and strong noise in the engine

Hello friends! Who can help me !!!!!!! Buy a subaru legacy b4 Turbo Motor EJ20 has about 20000kms hece very little changed the distribution strap without any problmea every success when at 3 days approx was walking without any problem at 2000rpm 40 kms/h when the engine is derived the engine and from Ai that does not surround it then I manage to make it walk and it has a noise that does not know where it does not come from That a very ugly cut rod, but the oil light does not turn on or in Chek Engine the engine turns it and it is not trancado it drains the oil and no metal particle came out they tell me that it can be some sensor but the noise is very ugly and I am afraid that maybe I can damage something

I can help me or can give me some information or experience

I am seeing your consultation, and in this regard, although I am not a mechanic, but a technician in automotive electronics, a few years ago I diagnosed a sub -Sj20, which had a somewhat ugly noise and made the engine vibrate, according to the revolutions they increased. The first vibrations appeared at approximately 1,400 rpm, and then appeared as a sub-listener of the frequency. After much turning through the electronic control systems, measuring the sensors and actuators with oscilloscope, I came to the conclusion that the noise was mechanical, the side of the engine in which it sounded was isolated, and it was determined to check the most basic. The cylinder head, taking the valve cover. As the engine has only one camshaft, it had the axis between the cylinders. When it turned, in the process of making progress, the axis that was broken made different forces between the cylinder of front with respect to De Besh, produced the noise and therefore the vibrations. The camshaft was changed, and solved matter.
I hope the experience serves you, and at least serve to advance a bit in the diagnosis, and you can reach port.
Greetings, from Valdivia, Andrés Fernández.