Whats up with these two codes any comon prob you guys see how do i start checking

 

its an o2 maxima by the way

 

Start from FSM page EC-167, copypaste below:

P0011 (Bank 1); P0021 (Bank 2)
- Intake valve timing control performance, There is a gap between angle of target and
phase-control angle degree.
Causes:
- Harness or connectors (Intake valve timing control solenoid valve circuit is open or shorted.)
- Intake valve timing control solenoid valve
- Crankshaft position sensor (POS)
- Camshaft position sensor (PHASE)
- Accumulation of debris to the signal pick-up portion of the camshaft

I'd add one possibility to the list: worn mech VTC parts if over 150k... possible if history contains lubrication problems. (Mech repair will be costly; i'd try locking the system in place.)
All electronics checkups start from voltage checks, at batt, at ECU. Then clean connectors, next test individual sensor inputs: see link p.14 below. Dig more/all info via 'Favorite Links', see link page below - top left corner:

Edit:
Btw. Checked the schema. Dunno why manual leaves these out from the problem list:
- 2pcs 15A fuses, 58/59, check first them
- second possibility is stuck relay, check, swap place with same color relay [E32]
- ctrl solenoid valve resistance 1 and 2: about 7ohms at 20°C (68°F)

 

The P0011 and P0021, Could be an oil leak flowing into the engine, or possibly the oxygen sensor near the catalytic converter is out....