Would I hear it if EM had cracked?

[Konstantin Bogach]

I am trying to find a reason for a laziness of my 200tq '89.  CIS
pressures ok, new injectors,  attains full boost (maybe slow), intake
air sensor is ok, exhaust  back pressure is ok. Ignition marks are in
place.  I don't know what else I can check in ignition system.
My guess is a leak of exhaust gases. I don't have an experience with
working on engines. How probable that valve is burnt or any other reason
for leak through valves?

Thank you.

Konstantin Bogach.