AE86 4age engine not starts crank ok backfires to air intake

[Ryo]

I made diagnostics with not running engine it shows nothing but when i start the engine it shows 11 impulses and than 4.5sec pause than again 11 impulses and it repeats. Trouble is that i don't see such error code in the chart in manual.
I have taken the hachi for a run. Put 10 liters of shell v power (100) in it and taken long run about 70km the car was running perfectly no discovery in power decrease. Response is good as well. So i have trouble to understand why it is that by 800rpm idle if i slowly push the gas pedal i feel the car shaking before it reaches about 1500rpm and it sounds like running on 3 cylinders and from exhaust i hear dum dum sound.
I want to find the cause before winter all was okay only thing i was doing was replacing hose from fuel filter to fuel rail and the pulsation damper. Nothing else was done.
I am thinking about:

- Doing compression test
- Cleaning the injectors putting them out and clean them with carb cleaner.
- Clean the EGR
- Clean the throttle body

I have no visible air leaks and i can say i made diagnostics on all parts regarding distributor, spark plugs, wires and coil nothing discovered wrong there.
It is first time i got troubles like this it is true the car had run not much last years i made a 500-1000km a year. Was not time to play with the hachi.
Anybody had some issues like this?