Hi guys,

sorry for opening this topic again, but I've searched almost everywhere and I can't find an answer to my problem.

For the past few months I'm getting some CELs and I found out that the car is running lean.

Codes I'm getting:
P1146 Heated O2 Sensor 2
P1147 Heated O2 Sensor 2
P1163 Heated O2 Sensor 1
P1164 Heated O2 Sensor 1
P0430 TW Catalyst System, Bank 2

OBD Live data:
-Both O2 sensors are running at 1.5V from idle to 6.6K RPM, with no significant drop in voltage (1.38-1.64) at WOT.
-When the throttle is released the peak is at 4.8V (no fuel).
-all 4 O2 sensors work properly (dynamic change in voltage)
-at idle the front O2 sensors show Rich AFR, the rear O2 sensor show Lean AFR.

What I observed:
-weird smell from the car...sulfurish with a pinch of gas
-when I changed the spark plugs, there was some white powder like residue on the tips
-moderate loss of torque (by feel)

Mods in the breathing system:
-K&N Typhoon CAI
-Invidia Gemini Catback
-Resonated test pipes (with CEL fix ada[ters)

I'm thinking that this might be fixed by changing the fuel pump for a higher pressure one, or by changing the gas pressure regulator and setting it to higher pressure, or getting a proper fuel map...

Where would you guys start?

Thanks for all the feedback.

Martin