P0170 Abnomal fuel system

Hi there, my '02 4G94 IO has this persistent code P0170. The CEL keeps coming and going. It all started with having bad fuel in the system, which I sorted it out but now the CEL keeps coming on and going off.

I have done the following changes yet still keep getting the same code.

1. Fuel pump in the tank was changed, got a reconditioned one

2. The high pressure GDI pump was changed as well, I used the one from a lancer since I couldn't get one for the IO. My original one had a low pressure of 2.8MPa.  It also ''leaked fuel'' in the engine as the oil had fuel in it.  The lancer replacement pressure ranges from 5.5MPa -5.7MPa. I have checked a thread on how to repair this pump and will do it for my pump that I removed.

3. All ignition coils are working well, though I changed 2 ignition boots with originals.

4. Spark plugs; I changed in September last year and are all working well. I have NGK BKR5EIX currently in use

5. I changed the injector nozzles (4) with reconditioned ones as well.

6. Changed the crankshaft position sensor as I had a code during these changes. the code has disappeared after the replacement.

7. Cleaned the EGR

Further, I have tested the front O2 sensor and is working fine. Another issue is that after driving for around an hour, and resting the vehicle for around 20minutes, the vehicle starts well, but has massive misfires, when I floor the accelaration pedal, no revs at all, until i floor it more then the revs pick up.

At times the idling gets rough when in trafiic.

Where could the issue be? any help? Could it be the ECU?